- Email: [email protected]
Prostaglandin synthases: Molecular characterization and involvement in prostaglandin biosynthesis
Accepted Manuscript Prostaglandin synthases: Molecular characterization involvement in prostaglandin biosynthesis
and
Min-Ju Seo, Deok-Kun Oh PII: DOI: Reference:
S0163-7827(16)30060-1 doi: 10.1016/j.plipres.2017.04.003 JPLR 941
To appear in:
Progress in Lipid Research
Received date: Revised date: Accepted date:
26 December 2016 30 March 2017 1 April 2017
Please cite this article as: Min-Ju Seo, Deok-Kun Oh , Prostaglandin synthases: Molecular characterization and involvement in prostaglandin biosynthesis. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Jplr(2017), doi: 10.1016/j.plipres.2017.04.003
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Prostaglandin synthases: Molecular characterization and
T
involvement in prostaglandin biosynthesis
CR
IP
Min-Ju Seo, Deok-Kun Oh*
US
Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of
PT
ED
M
AN
Korea
CE
* Corresponding author at: Department of Bioscience and Biotechnology, Konkuk University,
AC
120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea. E-mail address: [email protected] (D. K. Oh)
1
ACCEPTED MANUSCRIPT Contents Introduction Functions of prostaglandins Prostaglandin synthases 3.1. Prostaglandin G/H synthase 3.1.1. Enzyme properties 3.1.2. Mechanism and active site 3.2. Prostaglandin E synthase 3.2.1. Properties of cPGES 3.2.2. Properties of mPGESs 3.2.2. Mechanism and active site of mPGES-1 3.3. 15-Hydroxyprostaglandin dehydrogenase 3.3.1. Enzyme properties 3.3.2. Mechanism and active site 3.4. Prostaglandin D synthase 3.4.1. H-PGDS 3.4.2. L-PGDS 3.5. Prostaglandin F synthase 3.5.1. PGFS-1 3.5.2. PGFS-2 3.6. Prostaglandin I synthase 3.6.1. Enzyme properties 3.6.2. Mechanism and active site 3.7. Thromboxane A synthase 3.7.1. Enzyme properties 3.7.2. Mechanism and active site 4. Synthesis of prostaglandins 4.1. Chemical synthesis 4.2. Biosynthesis 4.2.1. Mammals 4.2.2. Corals 4.2.3. Florideae 4.2.4. Yeast and fungi 5. Future perspectives 5.1. Microbial expression systems for prostaglandin synthesis 5.2. Metabolic engineering for prostaglandin synthesis 6. Conclusion Reference
AC
CE
PT
ED
M
AN
US
CR
IP
T
1. 2. 3.
2
ACCEPTED MANUSCRIPT Abstract Prostaglandins (PGs) belong to a subclass of eicosanoids and are classified based on the structures of the cyclopentane ring and their number of double bonds in their hydrocarbon structures. PGs are important lipid mediators that are involved in inflammatory response. The
T
biosynthesis of diverse PGs from unsaturated C20 fatty acids containing at least three double
IP
bonds such as dihomo-γ-linoleic acid (20:3∆8Z,11Z,14Z), arachidonic acid (20:4∆5Z,8Z,11Z,14Z), and
CR
eicosapentaenoic acid (20:5∆5Z,8Z,11Z,14Z,17Z) is enables by various PG synthases, including prostaglandin H synthase (PGHS), 15-hydroxyprostaglandin dehydrogenase (15-HPGD), PGES,
US
PGDS, PGFS, PGIS, and thromboxane A synthase (TXAS). This review summarizes the
AN
biochemical properties, reaction mechanism, and active site details of PG synthases. Because PGs are involved in the immune system, an understanding of PG synthases is important in the
M
design of new anti-inflammatory drugs. The biosynthesis of PGs in various organisms, such as
ED
mammals, corals, florideae (a class of red algae), yeast, and fungi, is also introduced. The expression of PG synthases in the microbial systems for the synthesis of PGs is discussed. Now,
PT
the biosynthesis of PGs from glucose or glycerol is possible using metabolically engineered cells
AC
CE
expressing both unsaturated fatty acid-producing enzymes and PG synthases.
3
ACCEPTED MANUSCRIPT Abbreviation
AA, arachidonic acid; AKR, aldo-keto reductase; AOS, allene oxide synthase; CX, carbon numbers; COX, cyclooxygenase; cPGES, cytosolic PGE synthase; cPLA2, cytosolic
T
phospholipase A2; CYP, cytochrome P450; DGLA, dihomo-γ-linolenic acid; DP, prostaglandin
IP
D receptor; EGF-like, epidermal growth factor-like; EP, prostaglandin E receptor; EPA,
CR
eicosapentaenoic acid; ER, endoplasmic reticulum; Fet3, multicopper oxidase homolog; FP, prostaglandin F receptor; GSH, glutathione; GPCRs, G protein-coupled receptors; HETE,
US
hydroxyeicosatetraenoic acid; HEK, human embryonic kidney; HHT, hydroxyheptadecatrienoic
AN
acid; HPETE, hydroperoxyeicosatetraenic acid; HPGD, hydroxyprostaglandin dehydrogenase; H-PGDS, hematopoietic PGD synthase; Hsp, heat shock protein; IP, prostaglandin I receptor;
M
Lac1, laccase encoding gene; LOX, lipoxygenase; L-PGDS, lipocalin PGD synthase; MAPEG,
ED
membrane-associated proteins in eicosanoid and GSH metabolism; Me, methyl ester; mPGES, membrane-bound PGE synthase; Mw, molecular weight; NSAIDs, nonsteroidal anti-
PT
inflammatory drugs; NREM, non-rapid eye movement; Ole2, fatty acid desaturase homolog;
CE
PDB, protein data bank; PG, prostaglandin; PGA, prostaglandin A; PGB, prostaglandin B; PGC, prostaglandin C; PGD, prostaglandin D; PGE, prostaglandin E; PGF, prostaglandin F; PGG,
AC
prostaglandin G; PGH, prostaglandin H; PGI, prostaglandin I; PGJ, prostaglandin J; PGT, PG transporter; PGDS, prostaglandin D synthase; PGES, prostaglandin E synthase; PGFS, prostaglandin F synthase; PGHS, prostaglandin G/H synthase; PGIS, prostaglandin I synthase; POX, peroxidase; PPAR-γ, peroxisome proliferator activated receptor-γ; PUFA, polyunsaturated fatty acid; SDR, short-chain dehydrogenase/reductase; TP, thromboxane A receptor; TXA, thromboxane A; TXB, thromboxane B; TXAS, thromboxane A synthase.
4
ACCEPTED MANUSCRIPT 1. Introduction Polyunsaturated fatty acids (PUFAs), which belong to an important group of membrane lipids, are carboxylic acids containing 18-22 carbons (C18-C22) with double bonds of two or more. PUFAs are classified as n-3 (ω-3) and n-6 (ω-6) families depending on the position of the
T
first double bond at the end of PUFAs [1]. PUFAs can be metabolized into signaling compounds
IP
such as leukotrienes, lipoxins, resolvins, and protectins by enzymes in the lipoxygenase (LOX)
CR
pathway [2]. In another metabolic route, arachidonic acid (AA) is converted to prostaglandins (PGs), including PGH2, PGE2, 15-keto-PGE2, PGD2, PGF2α, PGI2, and thromboxane A2 (TXA2),
US
by enzymes in the cyclooxygenase (COX) pathway.
AN
PGs belong to a subclass of eicosanoids known as prostanoids. They contain C20 atoms, including a cyclopentane (5-carbon) ring. They are important secretory lipid mediators in
M
humans and other animals [3]. PGs have two are divided into two groups: prostacyclopentanes
ED
and thromboxanes. Prostacyclopentanes are classified based on the structures of their cyclopentane rings (denoted using a letter from A to K) and the number of double bonds in their
PT
hydrocarbon structures (denoted using a subscripted number from 1 to 3) [4], whereas
CE
thromboxanes consist of TXA and TXB (Fig. 1). PG was first found in seminal fluid in 1935 [5]. In 1950s, PG was first structurally characterized [6, 7]. PGF2α and PGE2 were totally
AC
synthesized using 20-step chemical reactions by E. J. Corey, who was awarded a Nobel Prize in 1990 [8]. Recently, PGF2α has been chemically synthesized using 7-step reactions [9]. PGs can also be biologically synthesized from dihomo-γ-linolenic acid
(DGLA), AA, and
eicosapentaenoic acid (EPA) by PG synthases using 2- or 3-step reactions. PGs are hormone-like chemical messenger that are involved in a diverse range of biological functions in humans. These include the regulation of the immune system, fever and pain
5
ACCEPTED MANUSCRIPT associated with inflammation, hemostasis, and blood pressure [10]. The biological importance of PGs has led to several review articles on their roles in biology, physiology, immunopathology, and pharmaceutics [10-18]. In mammalian cells, PGs are generated from membrane-released AA in response to cytokine, growth factors, and other pro-inflammatory stimuli, and AA is converted
T
to PGH2 via PGG2 as an intermediate by PGG/H synthase (PGHS) and diverse PGs are
IP
synthesized from PGH2 by other PG synthases, including PGE synthase (PGES), 15-
CR
hydroxyprostaglandin dehydrogenase (15-HPGD), PGD synthase (PGDS), PGF synthase (PGFS), PGI synthase (PGIS), and TXA synthase (TXAS). These mammalian PG synthases
US
convert the unsaturated fatty acids DGLA, AA, and EPA containing three, four, and five double
AN
bonds, respectively, to the PG products PGX1, PGX2, and PGX3 containing one, two, and three double bonds, respectively (Fig. 1). PGs are also found in various other non-mammals, including
M
aves (birds), actinopterygii (ray-finned fishes), kinetoplastida (trypanosomes), trematoda (blood-
ED
flukes), bivalvia (molluscs), malacostracas, corals, florideae (a class of red algae), fungi such as Mucoromycotina, Eurotiomycetes, Sordariomycetes, and Zygomycetes classes, and yeast such as
PT
Saccharomycetes and Tremellomycetes classes [19-25]. However, the biochemical properties of
CE
these non-mammalian enzymes and the biosynthesis of PGs in these organisms have not been reviewed thus far. Among the various organisms, only PG synthases suitable for microbial
AC
expression and applicable for PG biosynthesis are reviewed. This review article summarizes the biochemical properties, reaction mechanisms, and active site details of PG synthases as well as the biosynthesis of PGs in non-mammals. Additionally, the latter sections of this review introduce the application of microbial expression systems and metabolically engineered cells for the synthesis of PGs.
6
ACCEPTED MANUSCRIPT 2. Functions of prostaglandins PGs are produced in cells in response to external stimuli and act as autacoids within tissues via specific cell surface receptors and play a role in activating the inflammatory response [15]. PGs exert their inflammatory effects by binding to G protein-coupled receptors (GPCRs), also known
T
as seven-transmembrane domain receptors [26]. These receptors are involved in two principal
IP
signal transduction pathways: the cAMP and the phosphatidylinositol signaling pathways [27].
CR
PG receptors are divided into five basic types: PGE, PGD, PGF, PGI, and TXA receptors [16, 28]. The existence of diverse receptors indicates that PGs can activate a wide array of signal
US
transduction events in diverse cell types and modulating distinct biological effects (Table 1).
AN
PGE2 mediates cellular processes in pro-inflammatory and anti-inflammatory directions. PGE2 binds to PGE receptors, which exist as EP1, EP2, EP3, and EP4 subtypes, and is involved in pain
M
response, oogenesis, ovulation, fertilization, fever generation, and bone resorption [3, 15]. PGD2
ED
binds to two PGD receptors, DP1 and DP2 subtypes. This compound is involved in the regulation of the central nervous systems, pain non-rapid eye movement sleep (NREM) [29], and plays a
PT
role in chemotaxis and in allergy-induced asthma [30, 31]. PGF2α is an agonist for the PGF
CE
receptor and plays an important role in oogenesis, ovulation, luteolysis, contraction of uterine smooth muscle, and initiation of parturition [32, 33]. PGF2α is also used to induce labor and
AC
further functions as an abortifacient [9]. PGI2 is an agonist for the PGI receptors, IP1 and IP2. PGI2 is a potent vasodilator and an inhibitor of platelet aggregation. PGI2 plays a role in leukocyte adhesion, proliferation of vascular smooth muscle cells [34], and regulation of cardiovascular homeostasis [35]. TXA2, one of the most important prostanoids, can be defined as a lipid mediator that acts a vasoconstrictor, platelet activating agent, and modulates endothelial cell responses [36-39]. The
7
ACCEPTED MANUSCRIPT activity of TXA2 is mediated through two TXA receptors: TPα and TPβ. 15-Keto-PGE2 and ∆12,14
15-deoxy-PGJ2 act as agonist of peroxisome proliferator activated receptor-γ (PPAR-γ)
which inhibits tumor growth [40-42].
T
3. Prostaglandin synthases
IP
In this section, the biochemical properties, reaction mechanisms, and active site details of PG
CR
synthases are summarized. In vivo, AA is converted to PGH2 by PGHS. PGH2 is subsequently converted to a variety of PGs by several types of PG synthases (Fig. 2). PGES convert PGH2 to
US
PGE2, which is also a substrate of the enzyme 15-HPGD in the synthesis of 15-keto-PGE2. PGD2
AN
is synthesized from PGH2 by PGDS. PGF2α is produced from PGH2, PGD2, and PGE2 by three types of PGFS, including PGH 9,11-endoperoxide reductase (PGFS-1), PGD 11-ketoreductase
M
(PGFS-2), and PGE 9-ketoreductase (PGFS-3), respectively. PGE2, PGD2, and PGF2 are
ED
relatively stable in aqueous solution at pH 4.0−9.0, while both PGE2 and PGD2 are dehydrated at above pH 10.0 [43]. PGIS converts PGH2 to PGI2, which is unstable below pH 8.0 (half-life is 3
PT
min at pH 7.4 and 37 °C). The unstable PGI2 is hydrolyzed to a stable product, 6-keto-PGF1α.
CE
TXAS converts PGH2 to TXA2, which has a six-membered ring structure containing bicylic oxane-oxetane group. TXA2 (half-life is 30 s at pH 7.4 and 37 °C) is rapidly hydrolyzed to TXB2.
AC
Thus, the formation of PGI2 and TXA2 can be monitored by determining the levels of 6-ketoPGF1α and TXB2, respectively [7, 43]. PGA2, PGB2, and PGC2; and PGJ2 and
∆12,14
15-deoxy-
PGJ2 are formed from PGE2 and PGD2, respectively, by non-enzymatic reactions (Fig. 2). Phenotypes of PG synthases have been studied using knockout mice. PGHS-1 and PGHS-2 knockout mice show impaired inflammatory responses. PGHS-1 knockout mice exhibit the reduction of AA-induced ear edema and slightly inhibit macrophage recruitment, whereas
8
ACCEPTED MANUSCRIPT PGHS-2 knockout mice do not show the reduction and suppress acute inflammation. The peritonitis observes only in PGHS-2 knockout mice [44, 45]. Cytosolic PGE synthase (cPGES) knockout mice are perinatal lethal with poor lung development and delayed skin maturation [46, 47]. Membrane-bound PGE synthase-1 (mPGES-1) knockout mice exhibit impaired
T
inflammatory reactions and carcingogenesis suppression [48, 49], whereas mPGES-2 knockout
IP
mice show no specific phenotype [50]. Hematopoietic PGD synthase (H-PGDS) knockout mice
CR
exhibit the suppression of neuroinflammation, demyelination, and carcingogenesis [51-53]; and lipocalin PGD synthase (L-PGDS) knockout mice show impaired sleep regulation, pain sensation,
US
nephropathy, atherosclerosis, and obesity [29, 54-56]. PGFS knockout mice exhibit the
AN
deregulation of adipogenesis and lipogenesis [57]. PGIS knockout mice show high blood
ED
and impaired wound healing [59].
M
pressure and ischemic renal disorders [58]. TXAS knockout mice exhibit mild hemostatic defect
3.1. Prostaglandin G/H synthase
PT
PGHS (EC 1.14.99.1), commonly known as COX, converts AA to to PGH2 via PGG2 (Fig.
CE
3A). PGHS is a bifunctional enzyme with COX and peroxidase (POX) activities, which are responsible for the cyclization of AA and reduction of PGG2, respectively. PGG2 is also reduced
AC
rapidly by other chemical reducing agents because of their unstable nature. PGH2 itself is not physiological nor pharmacological active; instead, it serves as a precursor for other active PGs [3]. PGHS exists as two isoforms, namely PGHS-1 and PGHS-2, also known as COX-1 and COX-2, respectively [60]. Generally, PGHS-1 is expressed constitutively and serves in the regulation of vascular homeostasis and cellular responses to hormonal stimulation, whereas PGHS-2 is expressed
9
ACCEPTED MANUSCRIPT mainly in response to growth factors and inflammatory stimuli [11, 61]. However, PGHS-2 is also expressed in a constitutive manner in a specific tissue such as the kidney, gastrointestinal tract, human fetal brain, thymus, and stomach [62]. PGHS-1 and PGHS-2 are targets for nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit the activity of PGHS-1 and
T
PGHS-2, and thereby the synthesis of PGs, indicating that these lipid mediators are involved in
IP
the occurrence of pain, fever, and inflammation [11, 15]. Aspirin, diclofenac, ibupropen,
CR
indomethacin, meloxivam, and piroxicam are inhibitors for PGHSs [63]. NSAIDs are available for the inhibition of PGHS-1 and PGHS-2, although both enzymes have different selectivity for
US
NSAIDs [64]. PGHS-1 is inhibited by all NSAIDs, whereas PGHS-2 is inhibited by more
AN
specific inhibitors such as DuP697 [65], NS-398 [65], and SC-58125 [66]. PGHS-1 is inhibited by both time-dependent and time-independent inhibition mechanism, depending upon the
M
chemical nature of the inhibitor [67, 68], whereas PGHS-2 is inhibited by a time-dependent
ED
mechanism [69]. The different inhibition is due to the specific residue at position 523, an Ile in PGHS-1 and a Val in PGHS-2 [70, 71]. In addition, PGHS-1 activity is highly specific towards
PT
AA, which has a free carboxyl group, whereas PGHS-2 can efficiently use neutral ester and
CE
amide derivatives of AA as substrates [72].
AC
3.1.1. Enzyme properties
The amino acid sequences of PGHS-1 and PGHS-2 are highly conserved with approximately 90% sequence identity. PGHSs have four domains, including the epidermal growth factor-like (EGF-like), membrane binding, dimerization, and catalytic domains [24, 73]. The signal peptide at the N-terminus and the N-glycosylation sites at Asn68, Asn144, and Asn410 of PGHSs are important contributors to the proper folding of these enzymes [74]. The translation
10
ACCEPTED MANUSCRIPT rate of PGHS-1 is greater than that of PGHS-2 due to a difference in their signal peptides at the N-terminus. The signal peptide of PGHS-1 is in the range of 22 to 24 amino acids, while that of PGHS-2 is always 17 amino acids [11]. PGHS-2 has a instability motif, consisting of 27 amino acids at C-terminal region, which are involved in aspects of protein degradation [75]. The EGF-
T
like domain of PGHSs contains about 50 amino acids with less than 60% sequence identity
IP
between PGHS-1 and PGHS-2. The EGF-like domain also has seven cysteine residues that are
CR
involved in three intramolecular disulfide bonds and four disulfide linkages between the EGFlike and catalytic domains [76]. All PGHSs from mammals include the membrane binding
US
domain as an integral membrane protein, and thus detergent is required for protein solubilization
AN
[77]. The membrane binding domain of PGHSs provides an entrance to the active site [76]. The dimerization domain in PGHSs contributes to dimer assembly via hydrophobic interaction,
M
hydrogen bonding, and salt bridges; dimerization is essential for the catalytic activity of PGHSs
ED
[78]. The catalytic domain is the largest domain among the four domains in PGHSs. This domain contains spatially the distinct COX and POX active sites. The COX active site is located near the
PT
membrane binding domain, whereas the POX active site is located on the surface of the enzyme,
CE
furthest from the membrane binding domain. Arg120, which lies at the edge of the catalytic domain, is linked to the membrane binding domain and regulates access to the active site channel
AC
in PGHSs [76].
The biochemical properties of PGHSs, such as their specific activity, kinetic parameters, optimal temperature and pH, molecular weight, and quaternary structure are summarized in Table 2. PGHSs exist in various mammals including Bos taurus [79], Equus caballus [80], Homo sapiens [60, 81], Mus musculus [82, 83], Neovison vison [84], Oryctolagus cuniculus [85], Ovis aries [86, 87], and Rattus norvegicus [88, 89]. PGHSs also exist in non-mammals including the
11
ACCEPTED MANUSCRIPT aves Gallus gallus [90], the actinopterygii Danio rerio [91], the malacostracas Caprella sp. and Gammarus sp. [92], the corals Gersemia fruticosa [23] and Plexaura homomalla [93], and the florideae Gracilaria vermiculophylla [94]. The activities of PGHSs are generally determined at pH 7.2 or 8.0, and 25 or 37 °C. The kinetic parameters and specific activities of these enzymes
T
have been determined in only four organisms, H. sapiens [60, 81], O. aries [86], M. musculus
IP
[82, 83], and G. vermiculophylla [94]. Note also that the specific activity of O. aries PGHS for
CR
producing PGH2 from the substrate 15-hydroperoxyeicosatetraenic acid (15-HPETE) is measured using only the POX activity. In mammalian PGHSs, the specific activity for producing
US
PGH2 from AA of H. sapiens PGHS-1 is higher than that of M. musculus PGHS-1 or H. sapiens
AN
PGHS-2. However, the specific activity of G. vermiculophylla PGHS-1 was 6.5-fold higher than that of H. sapiens PGHS-1. Recombinant mammalian PGHSs are expressed in insect or yeast
M
host but not in bacterial host because of their lack of a glycosylation system needed for post-
ED
translational modifications of the active enzymes. In contrast, recombinant G. vermiculophylla PGHS-1 can be expressed in Escherichia coli because it does not have glycosylation sites. The
PT
quaternary structures of PGHSs from mammals are dimers, whereas PGHS from the florideae G.
CE
vermiculophylla is a tetramer. Mammalian PGHSs have a conserved binding site for NSAIDs, Arg120, Tyr355, and Ser530. However, the amino acid residues of the binding site of G.
AC
vermiculophylla PGHS-1 for NSAIDs are different with those of mammalian PGHSs, indicating that this enzyme has different inhibitors [94].
3.1.2. Mechanism and active site PGHS is a heme-dependent bifunctional enzyme that catalyzes the cyclization of AA and reduction of PGG2 to PGH2. The proposed reaction mechanism and three-dimensional (3D)
12
ACCEPTED MANUSCRIPT structure (Protein Date Base, PDB No. 1U67) of the active site of PGHS are presented in Fig. 3A. In the first step of PGHS reaction, the pro-S hydrogen abstraction is initiated at C13 of AA by a Tyr385 radical, generating pentadienyl radical between C11 and C15. O2 adds to C11 of the activated AA, resulting in the formation of an endoperoxide between C9 and C11, migration of
T
the carbon radical to C8, and coupling between C8 and C12 to form a cyclopentane ring. In the
IP
next step, the addition of a second O2 to the carbon radical at C15 yields a peroxyl radical, which
CR
formed after hydrogen abstraction by Tyr385 to make PGG2 containing a peroxyl group at C15, which is reduced to PGH2 by the POX activity of PGHS [95]. PGHS-1 from the florideae G.
US
vermiculophylla may have a similar reaction mechanism because the catalytic residue (Tyr385) as
AN
well as residues involved in heme liganding (His207 and His388), hydrogen abstraction (Tyr348 and Gly533), and cyclization (Val349 and Trp387) are absolutely conserved (Table 3). The Arg120
M
residue of mammalian PGHSs is critical for substrate and inhibitor binding as it is involved in
ED
opening the active site; and other residues are involved in substrate binding include Tyr355 and
PT
Ser530.
CE
3.2. Prostaglandin E synthase
PGES (EC 5.3.99.3) converts PGH2 to PGE2 (Fig. 3B) and has been identified only in
AC
mammals, although it can be easily expressed in E. coli. PGESs consist of cPGES, mPGES-1, and mPGES-2 [96]. Both cPGES and mPGES-2 are constitutively expressed. On the other hand, mPGES-1, a key enzyme for the in vivo conversion of PGH2 to PGE2, is involved in various pathophysiological events such as inflammation, fever, pain, female reproduction, tissue repair, and cancer [97], and mPGES-1 is co-regulated with PGHS-2 in A549 cells exposed to interleukin-1β [98]. To catalyze the conversion of AA to PGE2, which requires the sequential
13
ACCEPTED MANUSCRIPT reactions of two enzymes, mPGES-1 preferentially acts in concert with PGHS-2, whereas cPGES and mPGES-2 preferentially acts in concert with PGHS-1 [96]. Human embryonic kidney 293 (HEK293) cells co-expressing mPGES-1 and PGHS-2 produce approximately 2- to 4-fold higher
T
concentration of PGE2 from AA than cells expressing only mPGES-1 [99].
IP
3.2.1. Properties of cPGES
CR
cPGES, a 26 kDa cytosolic protein, has been identified as a heat shock protein 90 (Hsp90)associated protein because the enzyme is regulated by a Hsp (heat shock protein) with a
US
molecular weight (Mw) of 90 kDa. cPGES requires glutathione (GSH) as a cofactor for its
AN
enzymatic activity. cPGES has been found in Bombyx mori [100], D. rerio [101], and H. sapiens [102]. The specific activity and catalytic efficiency (kcat/Km) of H. sapiens cPGES are 0.19 µmol
M
min−1 mg−1 and 0.06 s−1 µM−1, respectively (Table 2). This enzyme is constitutively expressed
PT
3.2.2. Properties of mPGESs
ED
and is not affected by pro-inflammatory stimuli.
CE
mPGESs belong to a superfamily of membrane-associated proteins in eicosanoid and GSH metabolism (MAPEG). These enzymes also require GSH as a cofactor for activity. The MAPEG
AC
superfamily is found in prokaryotes and eukaryotes, however, mPGESs have been discovered only in mammals [103]. mPGES-1s are found in B. taurus [104], D. rerio [101], H. sapiens [97], M. musculus [105], and R. norvegicus [106], Sus scrofa [107]; and mPGES-2s exist in B. taurus [108], H. sapiens [109], Macaca fascicularis [109], and M. musculus [110] (Table 2). The Mws of mPGES-1s range from 15 to 18 kDa, whereas mPGES-2s have more than 30 kDa Mw. The specific activities and kinetic parameters for mPGESs are summarized in Table 2. The kinetic
14
ACCEPTED MANUSCRIPT parameters of mPGES-1s have been measured at pH 8.0 and 24 or 37 °C. The specific activity and catalytic efficiency (kcat/Km) of H. sapiens mPGES-1 [97] are the highest among mPGESs at 51.5 and 5.2-fold higher, respectively, than those of M. fascicularis mPGES-1 [109].
T
3.2.3. Mechanism and active site of mPGES-1
IP
The proposed reaction mechanism is based on the crystal structure of mPGES-1 from H.
CR
sapiens (PDB No. 4AL0) [111] (Fig. 3B). Ser127 of mPGES-1 activates the thiol group of the GSH cofactor, which in turn attacks the endoperoxide oxygen atom at C9 of PGH2, resulting in
US
the cleavage of the O−O bond and the formation of a S−O bond bridging C9 and the thiol group
AN
of GSH. Subsequent proton abstraction at C9 and S−O bond cleavage are mediated by Asp49 with the help of Arg126, resulting in the formation of PGE2 [106]. In the crystal structure, GSH in
M
the active site is coordinated by hydrogen bonds to the side chains of Arg73, Asn74, Glu77, His113,
ED
Tyr117, Arg126, and Ser127 (Fig. 3B). Ser127 of mPGES-1 serves as the catalytic residue; and Asp49
PT
and Arg126 form a salt-bridge and are involved in proton abstraction (Table 3).
CE
3.3. 15-Hydroxyprostaglandin dehydrogenase The conversion of PGE2 to 15-keto-PGE2 is catalyzed by 15-HPGD (EC 1.1.1.141), which
AC
belongs to the short-chain dehydrogenase/reductase (SDR) family (Fig. 3C). Two isoforms, 15HPGD-1 and 15-HPGD-2, have been identified for 15-HPGD. The cofactor of 15-HPGD-1 is NAD+, whereas 15-HPGD-2 uses NADP+ as cofactor. 15-HPGD-1 shows higher specificity toward PG and lipoxin substrates than 15-HPGD-2 [112].
3.3.1. Enzyme properties
15
ACCEPTED MANUSCRIPT 15-HPGDs have only been found in mammals, including B. taurus [113], H. sapiens [113, 114], M. musculus [115], O. cuniculus [116], R. norvegicus [117, 118], and S. scrofa [119]. The biochemical properties of 15-HPGDs are summarized in Table 2. Only 15-HPGD-1 is considered in this review because 15-HPGD-2 does not contribute to the catabolism of PGs [120]. In the
T
comparison of the sequences among the SDR family, 15-HPGD-1 has a well conserved Gly-rich
IP
motif (Gly-X-X-X-Gly-X-Gly) and catalytic triad (Ser-Tyr-Lys). The quaternary structure of 15-
CR
HPGD-1s is a dime with a Mw of 29 kDa. The activities of 15-HPGD-1s have been determined at pH 7.5 or 9.0 and 25 or 37 °C. Bos taurus 15-HPGD-1 has the highest specific activity [113],
M
3.3.2. Mechanism and active site
AN
sapiens 15-HPGD can be well expressed in E. coli.
US
whereas H. sapiens 15-HPGD-1 has the highest turnover number [112]. Notably, recombinant H.
ED
The reaction mechanism of 15-HPGD is presented in Fig. 3C. The catalytic residues Tyr151 and Ser138 are conserved residues in the SDR family (Table 3). Ser138 and Gln148 of 15-HPGD
PT
are involved in the formation of oxygen and hydrogen bonds at the C15 hydroxyl group of
CE
PGE2, respectively [112]. The hydroxyl group of the catalytic Tyr151 assists in the positioning of the C15 hydroxyl group of PGE2 with the help of Lys155. Deprotonation of the C15 hydroxyl
AC
group of PGE2 by Tyr151 and transfer of the hydrogen at C15 to NAD+ yield the product 15keto-PGE2. Based on the 3D structure (PDB No. 2GDZ) of the 15-HPGD active site, Thr11, Ile74, Asn91, Cys182, Val186, and Thr188 interact with the cofactor NAD+ [121].
3.4. Prostaglandin D synthase
16
ACCEPTED MANUSCRIPT PGDS (EC 5.3.99.2) converts PGH2 to PGD2 (Fig. 3D and 3E). PGDSs are classified into two types, H-PGDS and L-PGDS. H-PGDS requires GSH as a cofactor for catalysis because it is associated with the activity of glutathione-S-transferase [122]. Unlike to H-PGDS, L-PGDS does not required GSH as a cofactor; instead, it has an active site with a thiol group from a Cys
IP
T
residue [123].
CR
3.4.1. H-PGDS
H-PGDS is a therapeutic target protein for the design of anti-allergy and anti-inflammation
US
drugs. It is a cytosolic protein and has dimeric structure with a Mw of 23 kDa. H-PGDS binds
AN
not only GSH but also Mg2+ or Ca2+, which can increase the activity of H-PGDS. Binding of Mg2+ ions changes the affinity of H-PGDS for GSH, whereas binding of Ca2+ ions does not
M
change the affinity of H-PGDS [124]. The biochemical properties of H-PGDS are summarized in
ED
Table 2. H-PGDSs from H. sapiens, M. musculus, and R. norvegicus [125], and Schistosoma mansoni [22] have been reported, and their activities have been determined at pH 8.0 and 25 °C.
PT
Among the reported H-PGDSs, the specific activity of H-PGDS from R. norvegicus is the
CE
highest at 1.1-fold higher than that of H. sapiens. The reaction of H-PGDS is initiated by the binding of the thiolate anion of GSH to H-PGDS
AC
via the catalytic Tyr8 residue. The activated thiolate anion attacks the endoperoxide oxygen atom at C11 of PGH2 and forms a S−O bond. PGH2 is stabilized by a hydrogen bonding interaction between the amide nitrogen of glycine in GSH and the endoperoxide oxygen atom at C9 of PGH2. The labile S−O bond breaks to form a carbonyl group at C11 and to release the product PGD2 [124, 126] (Fig. 3D). The crystal structure of H-PGDS has been determined for the enzyme from H. sapiens (PDB No. 1IYH). In the active site, Tyr8, Arg14, and Trp104 are essential residues for
17
ACCEPTED MANUSCRIPT the activation, stabilization, and transfer of the thiol group in GSH, respectively, and other important residues include Asp93, Asp96, and Asp97, which are involved in metal coordination (Table 3).
T
3.4.2. L-PGDS
IP
L-PGDS was isolated from the rat brain [127]. It has a monomeric structure with a Mw of
CR
about 26 kDa. L-PGDS is identical to a beta-trace protein, and it is the first member of the lipocalin family and a major protein in human cerebrospinal fluid [128, 129]. L-PGDSs have
US
been reported in mammals, including B. taurus [130], H. sapiens [131], and M. musculus [132],
AN
and non-mammals, including D. rerio [101] and G. gallus [132], and their activities have been determined at pH 8.0 and 25 °C (Table 2). Among L-PGDSs, the specific activity of M. musculus
M
L-PGDS is the highest at 13.4-fold higher than that of R. norvegicus H-PGDS.
ED
The reaction mechanism of L-PGDS is similar to that of H-PGDS (Fig. 3E). The binding of PGH2 to the active site pocket of L-PGDS positions the endoperoxide oxygen at C-11 of PGH2 in
PT
close proximity to the thiol group of Cys65. The role of the Cys residue is the same as that of
CE
GSH in the reaction of H-PGDS. A S−O bond is formed at C11 of PGH2 by nucleophilic attack of thiolate anion of the catalytic Cys65 residue. The Ser45, Thr67, and Ser81 residues form a
AC
hydrogen bonding network that is involved in activating the thiol group of Cys65. The labile S−O bond is autonomously broken with proton rearrangement occurring at the hydroxyl group of Ser45, releasing the product PGD2. The Cys89 and Cys186 residues of L-PGDS form disulfide bridges, which plays an important role for the stabilization of the structure of L-PGDS [133]. Cys89 and Cys186 are conserved among many but not all lipocalin enzymes, whereas Cys65 is conserved in all lipocalin enzymes. Trp54 and His111 are involved in the release of PGD2.
18
ACCEPTED MANUSCRIPT
3.5. Prostaglandin F synthase PGFS (EC 1.1.1.188) is an enzyme that catalyzes the formation of PGF2α. PGFSs exist as three isoforms: PGFS-1, PGFS-2, and PGFS-3. PGFSs are classified based on their substrate. PGFS-1
T
and PGFS-3 convert PGH2 and PGE2 to PGF2α, respectively, while PGFS-2 converts PGD2 to
IP
9α,11β-PGF2α, which is a PGF2α stereoisomer. Most of these enzymes belong to the aldo-keto
CR
reductase (AKR) family, which requires NADPH as a cofactor. PGFS-1s from B. taurus [134], H. sapiens [135], Leishmania major [136], M. musculus [135, 137], S. scrofa [107, 137],
US
Trypanosoma brucei [138], and Trypanosoma cruzi [139]; PGFS-2s from B. taurus [140], and H.
AN
sapiens [141]; and PGFS-3 from S. scrofa [142] have been reported (Table 2). In this review, only PGFS-1 and PGFS-2 are introduced because the activity of PGFS-3 is similar to that of 15-
ED
M
HPGD.
3.5.1. PGFS-1
PT
PGFS-1 catalyzes the conversion of PGH2 to PGF2α, which requires NADPH or NADH as
CE
cofactor. PGFS-1s from various mammals and non-mammals have been identified (Table 2). PGFS-1 can be well expressed in E. coli. The specific activities and kinetic parameters of PGFS-
AC
1s have been determined at pH 7.0 or 7.5 and at 24, 25, or 27 °C. The specific activity and catalytic efficiency (kcat/Km) of PGFS-1 from T. brucei are 2 µmol min−1 mg−1 and 0.79 s−1 µM−1, respectively, which correspondingly represent the highest values for the conversion of PGH2 to PGF2α among the reported PGFS-1s [138]. The reaction mechanism and crystal structure of T. brucei PGFS-1 (PDB No. 1VBJ) are represented in Fig. 3F. The His110 residue of PGFS-1 and the cofactor NADPH are essential for
19
ACCEPTED MANUSCRIPT PGH2 reduction. Lys77 and Asp47 are involved in the protonation of His110, which is in turn positioned to allow a hydrogen bonding interactions to C9 or C11 endoperoxide oxygen of PGH2 (Table 2). As a result, PGH2 is protonated and reduced to PGF2α [74]. Among AKR family members, T. brucei PGFS-1 has a highly conserved catalytic tetrad that consists of the Asp47,
IP
T
Lys77, Try79, and His110 residues.
CR
3.5.2. PGFS-2
PGDS-2 catalyzes the conversion of PGH2 to 9α,11β-PGF2α that requires NADPH as a
US
cofactor. PGFS-2s have been identified in B. taurus [140] and H. sapiens [141]. However, the
AN
specific activity and kinetic parameters of PGFS-2 have only been determined in the enzyme from H. sapiens. The Mw of PGFS-2 from H. sapiens is 37 kDa. PGFS-2 catalyzes a reversible
M
reaction depending on the pH [143]. PGFS-2 catalyzes the reduction of PGD2 to PGF2 at low pH
ED
and the oxidation of PGF2 to PGD2 at high pH [144], and both reactions are affected by the presence of acidic or basic residues in the active site [141, 143, 145].
PT
The reaction of PGFS-2 is involved in a hydride transfer in PGFS-2 from NADPH to the
CE
carbonyl oxygen at C11 of PGD2. Tyr55 and His117 form hydrogen bonds to the C11 oxygen of cyclopentane of PGD2 (Table 3), which is protonated and reduced to 9α,11β-PGF2α [143] (Fig.
AC
3G). A catalytic tetrad consisting of Tyr55 and His117 in hydrogen bond networks to Asp50 and Lys84 provides an environment conducive for hydride transfer from the nicotinamide ring of NADPH [144].
3.6. Prostaglandin I synthase 3.6.1. Enzyme properties
20
ACCEPTED MANUSCRIPT PGIS (EC 5.3.99.4), also called as prostacyclin synthase or cytochrome P450 (CYP) 8A1, is a member of the CYP enzymes, which requires a heme group for catalysis. PGIS catalyzes the conversion of PGH2 to PGI2, which is non-enzymatically hydrated to yield 6-keto-PGF1α. PGISs have been identified in B. taurus [146], D. rerio [101], H. sapiens [147], M. musculus [148], and
T
R. norvegicus [149]. PGIS enzymes exist as a monomer with a Mw of 56 kDa (Table 2). The
IP
kinetic parameters and specific activities of these enzymes have been determined in B. taurus
CR
and H. sapiens at pH 7.5 and 23 °C. The specific activity of H. sapiens PGIS is 267-fold higher than that of B. taurus PGIS (Table 2). Notably, the specific activity of B. taurus PGIS was
US
determined using PGH2 as substrate, whereas the specific activity of H. sapiens PGIS was
AN
determined using U46619 as a substrate, which is a stable synthetic analog of PGH2.
ED
3.6.2. Mechanism and active site
M
Additionally, recombinant H. sapiens PGIS can be well expressed in E. coli [147].
In the reaction of PGIS, heme-iron (FeIII), which is coordinated by the thiolate anion of Cys441,
PT
transfers an electron to the endoperoxide oxygen atom at C11 of PGH2 to induce the cleavage of
CE
the O−O bond, resulting in the formation of a FeIV-porphyrin to oxygen bond at C11 and an alkoxy radical at C9 [150] (Fig. 3H). The alkoxy radical attacks the π-bond at the C6 and C9 to
AC
produce a five-member ring and a carbon radical at C5. The carbon radical at C5 then donates an electron to FeIV-porphyrin to form a C5 carbocation. Subsequent loss of the proton at C6 and formation of a double bond between C5 and C6 yield PGI2 [151]. Based on the crystal structure of H. sapiens PGIS (PDB No. 2IAG), Cys441 in the active site is involved in heme binding, and Ala447, which is located very close to Cys441, stabilizes the conformation of PGIS [147] (Table 3).
21
ACCEPTED MANUSCRIPT 3.7. Thromboxane A synthase 3.7.1 Enzyme properties TXAS (EC 5.3.99.5) catalyzes not only the conversion of PGH2 to TXA2 but also the cleavage of PGH2 to 12-hydroxy-heptadecatrienoic acid (12-HHT) and malondialdehyde, which are
T
formed stoichiometrically in the same amounts as TXA2 [152]. 12-HHT, an important lipid
IP
mediator of platelet plug formation, is formed by physiologically stimulated human platelets
CR
[153]. TXAS is a ferrihemoprotein and a member of CYP enzymes. TXASs have been identified in Danio rerio [101], H. sapiens [154], M. musculus [155, 156], R. norvegicus [157], and S.
US
scrofa [158]. H. sapiens TXAS can be well expressed in E. coli with the help of bacterial
AN
chaperones [159]. The Mw of TXAS is about 60 kDa. The kinetic parameters of TXASs have been determined at pH 7.5 and 23 or 30 °C (Table 2). The specific activity and Km value of H.
ED
M
sapiens TXAS were 52-and 1.7-fold higher, respectively, than those of S. scrofa TXAS.
3.7.2 Mechanism and active site
PT
The reaction mechanism of TXAS has been proposed based on the homology model of TXAS
CE
using Build Homology Models module in the MODELER application of Discovery Studio 4.0 (Accerlys, San Diego, CA, USA) constructed from the crystal structure of CYP from Bacillus
AC
megaterium as a template (PDB No. 1BU7) (Fig. 3I) [159]. The heme-iron (FeIII-porphyrin) in TXAS is coordinated to the thiolate anion of Cys480. The heme-iron reacts with the endoperoxide oxygen at C9 of PGH2 to induce cleavage of the O−O bond, resulting in the formation of a FeIVporphyrin and alkoxy radical at C11. The radical at C11 then donates an electron to FeIVporphyrin, resulting in the cleavage of C11 and C12 of the five-carbon ring and formation of an allylic radical, followed by ionic rearrangement to finally yield TXA2. The active site of TXAS
22
ACCEPTED MANUSCRIPT include Asn110, Arg413, and Arg478, which interact with the A- or D-ring of the heme, and Trp133 and Arg137 [160]. Additionally, Arg86, Phe127, Met237, and Leu521 of TXAS are involved in the stabilization of binding pocket [159] (Table 3)
T
4. Synthesis of prostaglandins
IP
4.1 Chemical synthesis
CR
Synthesis of PGs have been carried out via modified and improved chemical reactions based
US
on the use of Corey’s lactone as a synthetic intermediate. PGF2α is chemically synthesized through 20-step reactions which include Diels-Alder reaction, Baeyer-Villiger oxidation, Collins
AN
oxidation, Horner-Wadsworth-Emmons reaction, and Wittig reaction [8, 161]. In 2012, chemical
M
synthesis of PGF2α using 7-step reactions was developed [9]. Various types of PG analogues, including PGH2, PGE1, PGE2, PGF2α, and PGI2 analogues, have also been synthesized
ED
chemically [14]. PG analogues are designed to prostaglandin receptors, and have been used in
AC
4.2.1 Mammals
CE
4.2 Biosynthesis
PT
the treatment of open angle glaucoma, among other applications.
Mammalian PGs are the most widely studied and well characterized among PGs. The mammalian biosynthetic pathway from phospholipid to PGE2 is presented in Fig. 4. The starting material for synthesis of PGs, AA, is released from phospholipids of the endoplasmic reticulum (ER) and nuclear membrane by cytosolic phospholipase A2 (cPLA2), a key enzyme in eicosanoids production [162]. The released AA is metabolized to PGH2 via PGG2 by PGHS in the COX pathway. Various PGs in mammals are derived from PGH2 by PG synthases, including
23
ACCEPTED MANUSCRIPT PGHS, PGES, PGDS, PGFS, PGIS, and TXAS. PGE2 is synthesized from PGH2 by PGES in cells or by non-enzymatic reactions [163]. PGHS resides in the ER and nuclear membrane, and PGH2 is isomerized to various PGs by specific PG synthases in tissues. PGDS is found in brain and mast cells; PGFS is found in the uterus; PGIS is found in endothelium cells; and TXAS is
T
mainly found in platelets and macrophages [3]. PGs are released from cells by a PG transporter
IP
(PGT), and the released PGs then interact with the specific PG-receptors on cell surfaces. PGT is
CR
a lactate/PG anion exchanger [164], which mediates the energetically active uptake into the cell of PGE2, PGF2α, PGD2, and PGI2, but TXA2 [165]. PGT, a solute carrier organic anion
US
transporter family encoded by the SLCO2A1, is a member of the 12-membrane-spanning organic
AN
anion-transporting polypeptide superfamily of transporters. PGT has been discovered in R. norvegicus [166], M. musculus [167], and H. sapiens [168, 169]. PGT belongs to the organic
M
anion transporter family that has multi-specific system in substrate recognition due to its
PT
phosphorylation site [170].
ED
structure features such as 12-transmembrane domains and multiple glycosylation or
CE
4.2.2 Corals
In corals, biosynthesis of PGs from AA occurs by a different pathway than those of mammals
AC
and florideae [171, 172]. In Plexaura homomalla, AA is converted by 8-LOX to 8-HPETE, which is in turn transformed to clavulone I, a PG analogue, by the reactions of a fusion protein of 8-LOX and allene oxide synthase (AOS); and a putative cyclase (Fig. 4). Other major PGs that are found in P. homomalla include 15R-PGA2, 15R-PGA2-methyl ester (Me), 15R-acetate-PGA2Me, PGA2-Me, 15R-PGE2-Me and PGE2-Me [173-175]. The arctic coral Gersemia fruticosa, which has PGHS and 8-LOX-AOS enzymes, produces PGD2, PGE2, PGF2α, and 15-keto-PGF2α
24
ACCEPTED MANUSCRIPT from AA [176, 177]. P. homomalla 15R-PGHS and G. fruticosa PGHS have been cloned into Sf9 insect cells and characterized [23]. P. homomalla 15R-PGHS converts AA to 15R-PGE2, 15R-PGD2, and 15R-PGF2α via the intermediates 15R-PGG2 and 15R-PGH2, with 11R-HETE, 15R-HETE, and 12R-HHT as by-products [93]. The resulting 15R-PGE2 is converted to 15R-
T
acetate-PGA2-Me through the methylation and acetylation reactions by the commercial lipases
IP
from Candida antarctica and Humicola lanuginosa [178]. PGHS from G. fruticosa converts AA
CR
to PGE2, PGD2, and PGF2α with 11R-HETE, 15S-HETE, and HHT as by-products. This enzyme also catalyzes the production of several other PGs via the intermediates PGG2 and PGH2 from
US
AA, and the pathway for the biosynthesis of these other PGs is similar to that of 15R-PGHS from
AN
P. homomalla.
M
4.2.3 Florideae
ED
PGs have been discovered in various species of Gracilaria, which are a class of red algae. PGA2, PGE2, and 15-keto-PGE2 are found in G. asiatica, also known as G. verrucosa [179-181],
PT
and PGE2 and PGF2α are found in G. lichenoids [182]. Raw seaweed of G. gigas (10 g, w/w) is
CE
converts 2 mg AA to 4.9 µg PGE2 at 37 °C for 1 h, indicating that it has the enzymes to produce PGs [183]. PGA2, 8-iso-PGA2, PGE2, and 15-keto-PGE2 have all been identified by metabolic
AC
profiling of G. vermiculophylla [184, 185]. PGHS from G. vermiculophylla is the first nonmammalian PGHS to exhibit different enzyme properties compared to mammalian PGHSs. This enzyme can be expressed in E. coli without eukaryotic modifications [94, 186]. Recombinant E. coli expressing G. vermiculophylla PGHS can produce up to 2.7 mg/L PGF2α from exogenous AA without by-products like 11-hydroxyeicosatetraenoic acid (HETE) and 15-HETE [186]. PGF2α is also obtained from the reduction of PGH2 by SnCl2. The recombinant E. coli can
25
ACCEPTED MANUSCRIPT produce up to 130 mg/L of total PGs, which is the highest PGs production among cells [187]. Additionally, G. vermiculophylla PGHS also converts AA to PGE2, PGF2α, and PGD2 [94]. Levels of PG production by this algal enzyme is in the mg/L range, whereas mammalian PGHSs typically yield PGs in the ng/L range. This concentration difference may be due to the different
T
expression levels of algal and mammal PGHSs in E. coli, although the biosynthesis pathway of
CR
IP
PGs in florideae is similar to that of mammals.
4.2.4 Yeast and Fungi
US
The formation of PGs has been identified in pathogenic yeast and fungi. Pathogenic yeast,
AN
including the Saccharomycetes class, Candida albicans and Candida parapsilosis, and the Tremellomycetes class Cryptococcus neoformans, have the potential to influence immune
M
responses because they can produce immunomodulatory PGs from AA [188, 189]. C. albicans
ED
SC5314 produces 1 ng/L PGE2 from AA. Fatty acid desaturase homolog (Ole2) and multicopper oxidase homolog (Fet3) may be involved in the biosynthesis pathway of PGE2 in C. albicans
PT
because PGE2 production in ole2 or fet3-deficient strains is reduced to approximately 30% [190].
CE
However, Ole2 is not involved in the biosynthesis PGs in C. parapsilosis because PGE2 production in ole2-deficient mutant remains at similar level to that of the wild-type cells [189]. C.
AC
neoformans produces approximately 0.12 µg/L PGs including the PGE1−3 series and PGF2α [188]. The production of PGE2 and PGF2α by C. neoformans is inhibited by polyphenolic molecules such as caffeic acid, resveratrol, and nordihydroguaiaretic acid. These molecules have also been used as inhibitors of mammalian PG synthases. However, C. neoformans lacks PG synthases, although it does have a laccase. Laccase catalyzes the conversion of PGE2 from PGG2, however, is not involved in the conversion of AA to PGH2. Interestingly, loss of PG production is
26
ACCEPTED MANUSCRIPT observed in a laccase encoding gene (lac1)-deficient strain of C. neoformans [191], suggesting that the biosynthesis pathway of PGs in C. neoformans is different from those of mammals, corals, and florideae. Pathogenic fungi, including the Zygomycetes class Absidia corymbifera, the
T
Sordariomycetes class Fusarium dimerum and Sporothrix schenckii, the Eurotiomycetes class
IP
Aspergillus fumigatus, Blastomyces dermatitidis, Epidermophyton floccosum, Histoplasma
CR
capsulatum, Microsporum canis, Penicillium citrinum, Penicillium notatum, Penicillium piscarium, and the Mucoromycotina class Rhizopus pusillus produce 0.26−3.3 µg/L of PGE2,
US
PGF2α, and PGD2 when supplied with 302 mg/L AA [25]. However, the exact biosynthesis
AN
pathways of PGs in these fungi have yet to be characterized.
M
5. Future perspectives
ED
PGs have been manufactured by chemical synthesis. Several chemical methods have been developed to achieve for PGs synthesis. However, chemical methods are required at least 7-step
PT
reactions. In contrast, PGs can also be synthesized by biotechnological methods using PG
CE
synthases with 2- or 3-step reactions and recombinant cells expressing 2 or 3 PG synthases. However, the biotechnological methods for PGs synthesis are still in the early stage.
AC
Biotechnological methods have some advantages such as environmentally friendly, easy purification, stereospecific conversion, mild reaction conditions, and possible of large scale production with a high yield. Thus, in the future, PGs may be industrially produced using biotechnological methods. In this section, PGs synthesis using microbial expression systems are summarized. Moreover, metabolically engineered cells are suggested for PGs biosynthesis using microbial systems.
27
ACCEPTED MANUSCRIPT
5.1 Microbial expression systems for prostaglandin synthesis Generally, mammalian enzymes need post-translational modifications for activity and stability. Among PG synthases, PGHS requires N-glycosylation for full functional activity and therefore
T
cannot be expressed in E. coli, whereas PGES, 15-HPGD, PGDS, PGFS, PGIS, and TXAS can
IP
be heterologously expressed in E. coli. HEK293 and Chinese hamster ovary (CHO) cells, which
CR
are derived from mammals, have been used in the expression systems of PGHS. These hosts have some advantages, such as secretion of membrane enzymes and identical post-translational
US
modification for mammalian enzymes. However, they have also some disadvantages, such as
AN
expensive media, low enzyme expression levels, and difficulty in scale-up production. On the other hand, microbial expression systems, such as E. coli, Bacillus subtilis, Pichia pastoris,
M
Saccharomyces cerevisiae, and Aspergillus nidulans hosts, have been used extensively for the
ED
production of a diverse range of metabolites in industry applications because they have many advantages such as low cost, simple gene manipulation, easy and rapid expression, rapid growth,
PT
inexpensive medium, and simple culture conditions [192].
CE
PGHS-2 can be expressed at a high level in P. pastoris [193-195]. The co-expression of PGconverting enzyme with PGHS exhibits higher activity than the expression of PG-converting
AC
enzyme alone [99, 196]. The expression level of PGES in E. coli host is significantly increased by modifying the usage frequency of certain codons [197]. Coupled expression of PGHS with other PG-converting enzymes from M. musculus in S. cerevisiae has been used successfully to produce 6-keto-PGF1α, TXB2, and PGF2α from AA [198]. Recently, the expression of PGHS from G. vermiculophylla in E. coli has yielded the highest levels of PGs among PGHSs reported to date [187]. These results suggest that various PGs can be efficiently synthesized using coupled
28
ACCEPTED MANUSCRIPT expression system of G. vermiculophylla PGHS with other PG-converting enzymes. Therefore, non-mammalian sources of PG synthases and microbial expression systems may be the key to high-level production of PGs from AA.
T
5.2 Metabolic engineering for prostaglandin synthesis
IP
Although the conversion of DGLA, AA, and EPA to PGs by PG synthases has been
CR
demonstrated to be feasible, there are, however, limitations for the biosynthesis of PGs owing to the high costs of these substrates. Thus, allowing the synthesis of PGs to use inexpensive glucose
US
or glycerol through metabolic engineering is highly desirable from an economic standpoint. The
AN
enzymes related to the pathways for the conversion of acetyl-CoA to unsaturated fatty acids include acetyl-CoA carboxylase, fatty acid synthases, elongases, and desaturases [199] (Fig. 5).
M
Genes encoding these enzymes have been introduced into S. cerevisiae [200], Mortierella alpina
ED
[201-203], and Yarrowia lipolytica [204], and these cells are capable of producing unsaturated fatty acids, such as DGLA, AA, and EPA, from glucose or glycerol. Metabolically engineered M.
PT
alpina produces 4.9 and 2.9 g/L AA from glycerol and glucose, respectively [202, 203]. Because
CE
PG synthases convert unsaturated fatty acids such as DGLA, AA, and EPA to PGs, metabolically engineered cells expressing unsaturated fatty acid-producing enzymes together with PG
AC
synthases may be used for the inexpensive biosynthesis of PGs from glucose or glycerol.
6. Conclusion PGs are the important lipid mediators and are biosynthesized by PG synthases, including PGHS, PGES, 15-HPGD, PGDS, PGFS, PGIS, and TXAS. This review summarizes the biochemical properties, reaction mechanisms, and active site details of these PG synthases as
29
ACCEPTED MANUSCRIPT well as the biosynthesis of PGs in mammals, corals, florideae, and fungi. Although most PG synthases have been reported in mammals, similar enzymes can be found in yeast and fungi, as various PGs have been found in these organisms. PGHS from florideae has been expressed in E. coli, and this enzyme exhibits the highest activity among the reported PGHSs, indicating that the
T
non-mammalian enzyme sources and microbial expression systems may be the key to high-level
IP
production of PGs. Metabolically engineered microbial cells expressing unsaturated fatty acid-
CR
producing enzymes together with PG synthases may be used for the inexpensive biosynthesis of
US
PGs from glucose or glycerol.
AN
Acknowledgments
M
This study was funded by the Mid-Career Researcher Program, through the National Research
ED
Foundation grant funded by the Ministry of Science, ICT and Future Planning, Republic of
AC
CE
PT
Korea (No. 2016R1A2B3006881).
30
ACCEPTED MANUSCRIPT References [1] Leonard AE, Pereira SL, Sprecher H, Huang YS. Elongation of long-chain fatty acids. Prog Lipid Res 2004;43:36-54. [2] Horn T, Adel S, Schumann R, Sur S, Kakularam KR, Polamarasetty A, Redanna P, Kuhn H,
T
Heydeck D. Evolutionary aspects of lipoxygenases and genetic diversity of human leukotriene
IP
signaling. Prog Lipid Res 2015;57:13-39.
CR
[3] Funk CD. Prostaglandins and leukotrienes: advances in eicosanoid biology. Science
US
2001;294:1871-5.
[4] Buczynski MW, Dumlao DS, Dennis EA. Thematic Review Series: Proteomics. An integrated
AN
omics analysis of eicosanoid biology. J Lipid Res 2009;50:1015-38. [5] Von Euler US. To the knowledge of the pharmacological effects of native secretions and
M
extracts of male accessory glands. Naunyn Schmiedeberg's Arch Pharmacol 1934;175:78-84.
ED
[6] Bergstrom S, Sjovall J. The isolation of prostaglandin. Acta Chem Scand 1957;11:1086-1086.
PT
[7] Collins PW, Djuric SW. Synthesis of therapeutically useful prostaglandin and prostacyclin analogs. Chem Rev 1993;93:1533-1564.
CE
[8] Corey EJ, Weinshenker NM, Schaaf TK, Huber W. Stereo-controlled synthesis of prostaglandins F2α and E2 (dl). J Am Chem Soc 1969;91:5675-7.
AC
[9] Coulthard G, Erb W, Aggarwal VK. Stereocontrolled organocatalytic synthesis of prostaglandin PGF2α in seven steps. Nature 2012;489:278-81. [10] Harizi H, Corcuff JB, Gualde N. Arachidonic-acid-derived eicosanoids: roles in biology and immunopathology. Trends Mol Med 2008;14:461-9. [11] Simmons DL, Botting RM, Hla T. Cyclooxygenase isozymes: the biology of prostaglandin synthesis and inhibition. Pharmacol Rev 2004;56:387-437.
31
ACCEPTED MANUSCRIPT [12] Onguru O, Casey MB, Kajita S, Nakamura N, Lloyd RV. Cyclooxygenase-2 and thromboxane synthase in non-endocrine and endocrine tumors: a review. Endocr Pathol 2005;16:253-77. [13] Park JY, Pillinger MH, Abramson SB. Prostaglandin E2 synthesis and secretion: the role of
T
PGE2 synthases. Clin Immunol 2006;119:229-40.
CR
pulmonary arterial hypertension. Respir Med 2010;104:9-21.
IP
[14] Mubarak KK. A review of prostaglandin analogs in the management of patients with
[15] Ricciotti E, FitzGerald GA. Prostaglandins and inflammation. Arterioscler Thromb Vasc
US
Biol 2011;31:986-1000.
AN
[16] Hirata T, Narumiya S. Prostanoid receptors. Chem Rev 2011;111:6209-30. [17] Jiang J, Dingledine R. Prostaglandin receptor EP2 in the crosshairs of anti-inflammation,
M
anti-cancer, and neuroprotection. Trends Pharmacol Sci 2013;34:413-23.
ED
[18] Alhouayek M, Muccioli GG. COX-2-derived endocannabinoid metabolites as novel inflammatory mediators. Trends Pharmacol Sci 2014;35:284-92.
PT
[19] Cha YI, Solnica-Krezel L, DuBois RN. Fishing for prostanoids: deciphering the
CE
developmental functions of cyclooxygenase-derived prostaglandins. Dev Biol 2006;289:263-72. [20] Rowley AF, Vogan CL, Taylor GW, Clare AS. Prostaglandins in non-insectan invertebrates:
AC
recent insights and unsolved problems. J Exp Biol 2005;208:3-14. [21] Maizels RM, Yazdanbakhsh M. Immune regulation by helminth parasites: cellular and molecular mechanisms. Nat Rev Immunol 2003;3:733-44. [22] Herve M, Angeli V, Pinzar E, Wintjens R, Faveeuw C, Narumiya S, Capron A, Urade Y, Capron M, Riveau G, Trottein F. Pivotal roles of the parasite PGD2 synthase and of the host D prostanoid receptor 1 in schistosome immune evasion. Eur J Immunol 2003;33:2764-72.
32
ACCEPTED MANUSCRIPT [23] Koljak R, Jarving I, Kurg R, Boeglin WE, Varvas K, Valmsen K, Ustav M, Brash AR, Samel N. The basis of prostaglandin synthesis in coral: molecular cloning and expression of a cyclooxygenase from the Arctic soft coral Gersemia fruticosa. J Biol Chem 2001;276:7033-40. [24] Gupta K, Selinsky BS. Bacterial and algal orthologs of prostaglandin H(2)synthase: novel
T
insights into the evolution of an integral membrane protein. Biochim Biophys Acta
IP
2015;1848:83-94.
CR
[25] Noverr MC, Toews GB, Huffnagle GB. Production of prostaglandins and leukotrienes by pathogenic fungi. Infect Immun 2002;70:400-2.
US
[26] Trzaskowski B, Latek D, Yuan S, Ghoshdastider U, Debinski A, Filipek S. Action of
AN
molecular switches in GPCRs-theoretical and experimental studies. Curr Med Chem 2012;19:1090-109.
M
[27] Gilman AG. G proteins: transducers of receptor-generated signals. Annu Rev Biochem
ED
1987;56:615-49.
[28] Narumiya S, FitzGerald GA. Genetic and pharmacological analysis of prostanoid receptor
PT
function. J Clin Invest 2001;108:25-30.
CE
[29] Eguchi N, Minami T, Shirafuji N, Kanaoka Y, Tanaka T, Nagata A, Yoshida N, Urade Y, Ito S, Hayaishi O. Lack of tactile pain (allodynia) in lipocalin-type prostaglandin D synthase-
AC
deficient mice. Proc Natl Acad Sci U S A 1999;96:726-30. [30] Lewis RA, Soter NA, Diamond PT, Austen KF, Oates JA, Roberts LJ, 2nd. Prostaglandin D2 generation after activation of rat and human mast cells with anti-IgE. J Immunol 1982;129:162731. [31] Matsuoka T, Hirata M, Tanaka H, Takahashi Y, Murata T, Kabashima K, Sugimoto Y, Kobayashi T, Ushikubi F, Aze Y, Eguchi N, Urade Y, Yoshida N, Kimura K, Mizoguchi A, Honda
33
ACCEPTED MANUSCRIPT Y, Nagai H, Narumiya S. Prostaglandin D2 as a mediator of allergic asthma. Science 2000;287:2013-7. [32] Sugimoto Y, Yamasaki A, Segi E, Tsuboi K, Aze Y, Nishimura T, Oida H, Yoshida N, Tanaka T, Katsuyama M, Hasumoto K, Murata T, Hirata M, Ushikubi F, Negishi M, Ichikawa A,
T
Narumiya S. Failure of parturition in mice lacking the prostaglandin F receptor. Science
IP
1997;277:681-3.
CR
[33] Saito O, Guan Y, Qi Z, Davis LS, Komhoff M, Sugimoto Y, Narumiya S, Breyer RM, Breyer MD. Expression of the prostaglandin F receptor (FP) gene along the mouse genitourinary
US
tract. Am J Physiol Renal Physiol 2003;284:F1164-70.
AN
[34] Noda M, Kariura Y, Pannasch U, Nishikawa K, Wang L, Seike T, Ifuku M, Kosai Y, Wang B, Nolte C. Neuroprotective role of bradykinin because of the attenuation of pro-inflammatory
M
cytokine release from activated microglia. J Neurochem 2007;101:397-410.
ED
[35] Kawabe J, Ushikubi F, Hasebe N. Prostacyclin in vascular diseases. - Recent insights and future perspectives. Circ J 2010;74:836-43.
CE
Fed Proc 1987;46:133-8.
PT
[36] Ogletree ML. Overview of physiological and pathophysiological effects of thromboxane A2.
[37] Hirata M, Hayashi Y, Ushikubi F, Yokota Y, Kageyama R, Nakanishi S, Narumiya S.
20.
AC
Cloning and expression of cDNA for a human thromboxane A2 receptor. Nature 1991;349:617-
[38] Jones DA, Fitzpatrick FA. Thromboxane A2 synthase. Modification during "suicide" inactivation. J Biol Chem 1991;266:23510-4. [39] Feletou M, Vanhoutte PM, Verbeuren TJ. The thromboxane/endoperoxide receptor (TP): the common villain. J Cardiovasc Pharmacol 2010;55:317-32.
34
ACCEPTED MANUSCRIPT [40] Harmon GS, Lam MT, Glass CK. PPARs and lipid ligands in inflammation and metabolism. Chem Rev 2011;111:6321-40. [41] Lu D, Han C, Wu T. 15-hydroxyprostaglandin dehydrogenase-derived 15-ketoprostaglandin E2 inhibits cholangiocarcinoma cell growth through interaction with PPARγ,
T
SMAD2/3, and TAP63 proteins. J Biol Chem 2013;288:19484-502.
IP
[42] Lu D, Han C, Wu T. 15-PGDH inhibits hepatocellular carcinoma growth through 15-keto-
CR
PGE2/PPARγ-mediated activation of p21WAF1/Cip1. Oncogene 2014;33:1101-12.
pathways. New Compr Biochem 2002;36:341-371.
US
[43] Smith WL, Murphy RC. The eicosanoids: cyclooxygenase, lipoxygenase, and epoxygenase
AN
[44] Morham SG, Langenbach R, Loftin CD, Tiano HF, Vouloumanos N, Jennette JC, Mahler JF, Kluckman KD, Ledford A, Lee CA, Smithies O. Prostaglandin synthase 2 gene disruption causes
M
severe renal pathology in the mouse. Cell 1995;83:473-82.
ED
[45] Langenbach R, Loftin C, Lee C, Tiano H. Cyclooxygenase knockout mice: models for elucidating isoform-specific functions. Biochem Pharmacol 1999;58:1237-46.
PT
[46] Grad I, McKee TA, Ludwig SM, Hoyle GW, Ruiz P, Wurst W, Floss T, Miller CA, 3rd,
2006;26:8976-83.
CE
Picard D. The Hsp90 cochaperone p23 is essential for perinatal survival. Mol Cell Biol
AC
[47] Nakatani Y, Hokonohara Y, Kakuta S, Sudo K, Iwakura Y, Kudo I. Knockout mice lacking cPGES/p23, a constitutively expressed PGE2 synthetic enzyme, are peri-natally lethal. Biochem Biophys Res Commun 2007;362:387-92. [48] Trebino CE, Stock JL, Gibbons CP, Naiman BM, Wachtmann TS, Umland JP, Pandher K, Lapointe JM, Saha S, Roach ML, Carter D, Thomas NA, Durtschi BA, McNeish JD, Hambor JE, Jakobsson PJ, Carty TJ, Perez JR, Audoly LP. Impaired inflammatory and pain responses in mice
35
ACCEPTED MANUSCRIPT lacking an inducible prostaglandin E synthase. Proc Natl Acad Sci U S A 2003;100:9044-9. [49] Sasaki Y, Kamei D, Ishikawa Y, Ishii T, Uematsu S, Akira S, Murakami M, Hara S. Microsomal prostaglandin E synthase-1 is involved in multiple steps of colon carcinogenesis. Oncogene 2012;31:2943-52.
T
[50] Jania LA, Chandrasekharan S, Backlund MG, Foley NA, Snouwaert J, Wang IM, Clark P,
IP
Audoly LP, Koller BH. Microsomal prostaglandin E synthase-2 is not essential for in vivo
CR
prostaglandin E2 biosynthesis. Prostaglandins Other Lipid Mediat 2009;88:73-81. [51] Rajakariar R, Hilliard M, Lawrence T, Trivedi S, Colville-Nash P, Bellingan G, Fitzgerald
US
D, Yaqoob MM, Gilroy DW. Hematopoietic prostaglandin D2 synthase controls the onset and
AN
resolution of acute inflammation through PGD2 and 15-deoxy∆12-14 PGJ2. Proc Natl Acad Sci U S A 2007;104:20979-84.
M
[52] Trivedi SG, Newson J, Rajakariar R, Jacques TS, Hannon R, Kanaoka Y, Eguchi N,
ED
Colville-Nash P, Gilroy DW. Essential role for hematopoietic prostaglandin D2 synthase in the control of delayed type hypersensitivity. Proc Natl Acad Sci U S A 2006;103:5179-84.
PT
[53] Murata T, Aritake K, Matsumoto S, Kamauchi S, Nakagawa T, Hori M, Momotani E, Urade
CE
Y, Ozaki H. Prostagladin D2 is a mast cell-derived antiangiogenic factor in lung carcinoma. Proc Natl Acad Sci U S A 2011;108:19802-7.
AC
[54] Pinzar E, Kanaoka Y, Inui T, Eguchi N, Urade Y, Hayaishi O. Prostaglandin D synthase gene is involved in the regulation of non-rapid eye movement sleep. Proc Natl Acad Sci U S A 2000;97:4903-4907. [55] Miwa Y, Takiuchi S, Kamide K, Yoshii M, Horio T, Tanaka C, Banno M, Miyata T, Sasaguri T, Kawano Y. Identification of gene polymorphism in lipocalin-type prostaglandin D synthase and its association with carotid atherosclerosis in Japanese hypertensive patients. Biochem
36
ACCEPTED MANUSCRIPT Biophys Res Commun 2004;322:428-33. [56] Ragolia L, Palaia T, Hall CE, Maesaka JK, Eguchi N, Urade Y. Accelerated glucose intolerance, nephropathy, and atherosclerosis in prostaglandin D2 synthase knock-out mice. J Biol Chem 2005;280:29946-55.
T
[57] Volat FE, Pointud JC, Pastel E, Morio B, Sion B, Hamard G, Guichardant M, Colas R,
IP
Lefrancois-Martinez AM, Martinez A. Depressed levels of prostaglandin F2α in mice lacking
CR
Akr1b7 increase basal adiposity and predispose to diet-induced obesity. Diabetes 2012;61:2796806.
US
[58] Yokoyama C, Yabuki T, Shimonishi M, Wada M, Hatae T, Ohkawara S, Takeda J, Kinoshita
AN
T, Okabe M, Tanabe T. Prostacyclin-deficient mice develop ischemic renal disorders, including nephrosclerosis and renal infarction. Circulation 2002;106:2397-403.
M
[59] Yu IS, Lin SR, Huang CC, Tseng HY, Huang PH, Shi GY, Wu HL, Tang CL, Chu PH, Wang
ED
LH, Wu KK, Lin SW. TXAS-deleted mice exhibit normal thrombopoiesis, defective hemostasis, and resistance to arachidonate-induced death. Blood 2004;104:135-42.
PT
[60] Zou H, Yuan C, Dong L, Sidhu RS, Hong YH, Kuklev DV, Smith WL. Human
CE
cyclooxygenase-1 activity and its responses to COX inhibitors are allosterically regulated by nonsubstrate fatty acids. J Lipid Res 2012;53:1336-47.
AC
[61] Smith T, Leipprandt J, DeWitt D. Purification and characterization of the human recombinant histidine-tagged prostaglandin endoperoxide H synthases-1 and -2. Arch Biochem Biophys 2000;375:195-200. [62] Kirkby NS, Chan MV, Zaiss AK, Garcia-Vaz E, Jiao J, Berglund LM, Verdu EF, AhmetajShala B, Wallace JL, Herschman HR, Gomez MF, Mitchell JA. Systematic study of constitutive cyclooxygenase-2 expression: Role of NF-kappaB and NFAT transcriptional pathways. Proc Natl
37
ACCEPTED MANUSCRIPT Acad Sci U S A 2016;113:434-9. [63] Frolich JC. Prostaglandin endoperoxide synthetase isoenzymes: the clinical relevance of selective inhibition. Ann Rheum Dis 1995;54:942-3. [64] Smith WL, Meade EA, DeWitt DL. Interactions of PGH synthase isozymes-1 and -2 with
T
NSAIDs. Ann N Y Acad Sci 1994;744:50-7.
IP
[65] Copeland RA, Williams JM, Giannaras J, Nurnberg S, Covington M, Pinto D, Pick S,
synthase. Proc Natl Acad Sci U S A 1994;91:11202-6.
CR
Trzaskos JM. Mechanism of selective inhibition of the inducible isoform of prostaglandin G/H
US
[66] Seibert K, Zhang Y, Leahy K, Hauser S, Masferrer J, Perkins W, Lee L, Isakson P.
AN
Pharmacological and biochemical demonstration of the role of cyclooxygenase 2 in inflammation and pain. Proc Natl Acad Sci U S A 1994;91:12013-7.
M
[67] Rome LH, Lands WE. Structural requirements for time-dependent inhibition of
ED
prostaglandin biosynthesis by anti-inflammatory drugs. Proc Natl Acad Sci U S A 1975;72:48635.
PT
[68] Blobaum AL, Marnett LJ. Structural and functional basis of cyclooxygenase inhibition. J
CE
Med Chem 2007;50:1425-41.
[69] Ouellet M, Percival MD. Effect of inhibitor time-dependency on selectivity towards
AC
cyclooxygenase isoforms. Biochem J 1995;306 ( Pt 1):247-51. [70] Gierse JK, McDonald JJ, Hauser SD, Rangwala SH, Koboldt CM, Seibert K. A single amino acid difference between cyclooxygenase-1 (COX-1) and -2 (COX-2) reverses the selectivity of COX-2 specific inhibitors. J Biol Chem 1996;271:15810-4. [71] Bertolini A, Ottani A, Sandrini M. Selective COX-2 inhibitors and dual acting antiinflammatory drugs: critical remarks. Curr Med Chem 2002;9:1033-43.
38
ACCEPTED MANUSCRIPT [72] Rouzer CA, Marnett LJ. Endocannabinoid oxygenation by cyclooxygenases, lipoxygenases, and cytochromes P450: cross-talk between the eicosanoid and endocannabinoid signaling pathways. Chem Rev 2011;111:5899-921. [73] Kulmacz RJ, van der Donk WA, Tsai AL. Comparison of the properties of prostaglandin H
T
synthase-1 and -2. Prog Lipid Res 2003;42:377-404.
IP
[74] Smith WL, Urade Y, Jakobsson PJ. Enzymes of the cyclooxygenase pathways of prostanoid
CR
biosynthesis. Chem Rev 2011;111:5821-65.
[75] Kang YJ, Mbonye UR, DeLong CJ, Wada M, Smith WL. Regulation of intracellular
US
cyclooxygenase levels by gene transcription and protein degradation. Prog Lipid Res
AN
2007;46:108-25.
[76] Picot D, Loll PJ, Garavito RM. The X-ray crystal structure of the membrane protein
M
prostaglandin H2 synthase-1. Nature 1994;367:243-9.
ED
[77] Miyamoto T, Ogino N, Yamamoto S, Hayaishi O. Purification of prostaglandin endoperoxide synthetase from bovine vesicular gland microsomes. J Biol Chem 1976;251:2629-
PT
36.
CE
[78] Dong L, Vecchio AJ, Sharma NP, Jurban BJ, Malkowski MG, Smith WL. Human cyclooxygenase-2 is a sequence homodimer that functions as a conformational heterodimer. J
AC
Biol Chem 2011;286:19035-46. [79] Asselin E, Drolet P, Fortier M. Cellular mechanisms involved during oxytocin-induced prostaglandin F2α production in endometrial epithelial cells in vitro: role of cyclooxygenase-2. Endocrinology 1997;138:4798-805. [80] Boerboom D, Sirois J. Molecular characterization of equine prostaglandin G/H synthase-2 and regulation of its messenger ribonucleic acid in preovulatory follicles. Endocrinology
39
ACCEPTED MANUSCRIPT 1998;139:1662-70. [81] Gierse JK, Hauser SD, Creely DP, Koboldt C, Rangwala SH, Isakson PC, Seibert K. Expression and selective inhibition of the constitutive and inducible forms of human cyclooxygenase. Biochem J 1995;305 ( Pt 2):479-84.
T
[82] DeWitt DL, el-Harith EA, Kraemer SA, Andrews MJ, Yao EF, Armstrong RL, Smith WL.
Biol Chem 1990;265:5192-8.
CR
IP
The aspirin and heme-binding sites of ovine and murine prostaglandin endoperoxide synthases. J
[83] Vecchio AJ, Simmons DM, Malkowski MG. Structural basis of fatty acid substrate binding
US
to cyclooxygenase-2. J Biol Chem 2010;285:22152-63.
AN
[84] Song JH, Sirois J, Houde A, Murphy BD. Cloning, developmental expression, and immunohistochemistry of cyclooxygenase 2 in the endometrium during embryo implantation and
M
gestation in the mink (Mustela vison). Endocrinology 1998;139:3629-36.
ED
[85] Guan Y, Chang M, Cho W, Zhang Y, Redha R, Davis L, Chang S, DuBois RN, Hao CM, Breyer M. Cloning, expression, and regulation of rabbit cyclooxygenase-2 in renal medullary
PT
interstitial cells. Am J Physiol 1997;273:F18-26.
CE
[86] Liu J, Seibold SA, Rieke CJ, Song I, Cukier RI, Smith WL. Prostaglandin endoperoxide H synthases: peroxidase hydroperoxide specificity and cyclooxygenase activation. J Biol Chem
AC
2007;282:18233-44.
[87] Johnson JL, Wimsatt J, Buckel SD, Dyer RD, Maddipati KR. Purification and characterization of prostaglandin H synthase-2 from sheep placental cotyledons. Arch Biochem Biophys 1995;324:26-34. [88] Feng L, Sun W, Xia Y, Tang WW, Chanmugam P, Soyoola E, Wilson CB, Hwang D. Cloning two isoforms of rat cyclooxygenase: differential regulation of their expression. Arch
40
ACCEPTED MANUSCRIPT Biochem Biophys 1993;307:361-8. [89] Kennedy BP, Chan CC, Culp SA, Cromlish WA. Cloning and expression of rat prostaglandin endoperoxide synthase (cyclooxygenase)-2 cDNA. Biochem Biophys Res Commun 1993;197:494-500.
T
[90] Xie WL, Chipman JG, Robertson DL, Erikson RL, Simmons DL. Expression of a mitogen-
IP
responsive gene encoding prostaglandin synthase is regulated by mRNA splicing. Proc Natl Acad
CR
Sci U S A 1991;88:2692-6.
[91] Grosser T, Yusuff S, Cheskis E, Pack MA, FitzGerald GA. Developmental expression of
US
functional cyclooxygenases in zebrafish. Proc Natl Acad Sci U S A 2002;99:8418-23.
AN
[92] Varvas K, Kurg R, Hansen K, Jarving R, Jarving I, Valmsen K, Lohelaid H, Samel N. Direct evidence of the cyclooxygenase pathway of prostaglandin synthesis in arthropods: genetic and
M
biochemical characterization of two crustacean cyclooxygenases. Insect Biochem Mol Biol
ED
2009;39:851-60.
[93] Valmsen K, Jarving I, Boeglin WE, Varvas K, Koljak R, Pehk T, Brash AR, Samel N. The
PT
origin of 15R-prostaglandins in the Caribbean coral Plexaura homomalla: molecular cloning and
CE
expression of a novel cyclooxygenase. Proc Natl Acad Sci U S A 2001;98:7700-5. [94] Varvas K, Kasvandik S, Hansen K, Jarving I, Morell I, Samel N. Structural and catalytic
AC
insights into the algal prostaglandin H synthase reveal atypical features of the first non-animal cyclooxygenase. Biochimica Et Biophysica Acta-Molecular and Cell Biology of Lipids 2013;1831:863-871. [95] Hamberg M, Samuelsson B. Detection and isolation of an endoperoxide intermediate in prostaglandin biosynthesis. Proc Natl Acad Sci U S A 1973;70:899-903. [96] Samuelsson B, Morgenstern R, Jakobsson PJ. Membrane prostaglandin E synthase-1: a
41
ACCEPTED MANUSCRIPT novel therapeutic target. Pharmacol Rev 2007;59:207-24. [97] Thoren S, Weinander R, Saha S, Jegerschold C, Pettersson PL, Samuelsson B, Hebert H, Hamberg M, Morgenstern R, Jakobsson PJ. Human microsomal prostaglandin E synthase-1: purification, functional characterization, and projection structure determination. J Biol Chem
T
2003;278:22199-209.
IP
[98] Thoren S, Jakobsson PJ. Coordinate up- and down-regulation of glutathione-dependent
CR
prostaglandin E synthase and cyclooxygenase-2 in A549 cells. Inhibition by NS-398 and leukotriene C4. Eur J Biochem 2000;267:6428-34.
US
[99] Murakami M, Nakatani Y, Tanioka T, Kudo I. Prostaglandin E synthase. Prostaglandins
AN
Other Lipid Mediat 2002;68-69:383-99.
[100] Yamamoto K, Suzuki M, Higashiura A, Aritake K, Urade Y, Uodome N, Hossain T,
M
Nakagawa A. New insights into the catalytic mechanism of Bombyx mori prostaglandin E
ED
synthase gained from structure-function analysis. Biochemical and Biophysical Research Communications 2013;440:762-767.
PT
[101] Yeh HC, Wang LH. Profiling of prostanoids in zebrafish embryonic development.
CE
Prostaglandins Leukot Essent Fatty Acids 2006;75:397-402. [102] Tanioka T, Nakatani Y, Semmyo N, Murakami M, Kudo I. Molecular identification of
AC
cytosolic prostaglandin E2 synthase that is functionally coupled with cyclooxygenase-1 in immediate prostaglandin E2 biosynthesis. J Biol Chem 2000;275:32775-82. [103] Bresell A, Weinander R, Lundqvist G, Raza H, Shimoji M, Sun TH, Balk L, Wiklund R, Eriksson J, Jansson C, Persson B, Jakobsson PJ, Morgenstern R. Bioinformatic and enzymatic characterization of the MAPEG superfamily. FEBS J 2005;272:1688-703. [104] Filion F, Bouchard N, Goff AK, Lussier JG, Sirois J. Molecular cloning and induction of
42
ACCEPTED MANUSCRIPT bovine prostaglandin E synthase by gonadotropins in ovarian follicles prior to ovulation in vivo. J Biol Chem 2001;276:34323-30. [105] Lazarus M, Kubata BK, Eguchi N, Fujitani Y, Urade Y, Hayaishi O. Biochemical characterization of mouse microsomal prostaglandin E synthase-1 and its colocalization with
T
cyclooxygenase-2 in peritoneal macrophages. Arch Biochem Biophys 2002;397:336-41.
and
up-regulation
of
inducible
rat
prostaglandin
CR
expression,
IP
[106] Mancini JA, Blood K, Guay J, Gordon R, Claveau D, Chan CC, Riendeau D. Cloning, E
synthase
during
lipopolysaccharide-induced pyresis and adjuvant-induced arthritis. J Biol Chem 2001;276:4469-
US
75.
AN
[107] Waclawik A, Rivero-Muller A, Blitek A, Kaczmarek MM, Brokken LJ, Watanabe K, Rahman NA, Ziecik AJ. Molecular cloning and spatiotemporal expression of prostaglandin F
M
synthase and microsomal prostaglandin E synthase-1 in porcine endometrium. Endocrinology
ED
2006;147:210-21.
[108] Watanabe K, Kurihara K, Suzuki T. Purification and characterization of membrane-bound
PT
prostaglandin E synthase from bovine heart. Biochim Biophys Acta 1999;1439:406-14.
CE
[109] Tanikawa N, Ohmiya Y, Ohkubo H, Hashimoto K, Kangawa K, Kojima M, Ito S, Watanabe K. Identification and characterization of a novel type of membrane-associated
AC
prostaglandin E synthase. Biochem Biophys Res Commun 2002;291:884-9. [110] Murakami M, Nakashima K, Kamei D, Masuda S, Ishikawa Y, Ishii T, Ohmiya Y, Watanabe K, Kudo I. Cellular prostaglandin E2 production by membrane-bound prostaglandin E synthase-2 via both cyclooxygenases-1 and -2. J Biol Chem 2003;278:37937-47. [111] Sjogren T, Nord J, Ek M, Johansson P, Liu G, Geschwindner S. Crystal structure of microsomal prostaglandin E2 synthase provides insight into diversity in the MAPEG superfamily.
43
ACCEPTED MANUSCRIPT Proc Natl Acad Sci U S A 2013;110:3806-11. [112] Cho H, Huang L, Hamza A, Gao D, Zhan CG, Tai HH. Role of glutamine 148 of human 15-hydroxyprostaglandin dehydrogenase in catalytic oxidation of prostaglandin E2. Bioorg Med Chem 2006;14:6486-91.
T
[113] Parent M, Madore E, MacLaren LA, Fortier MA. 15-Hydroxyprostaglandin dehydrogenase
IP
in the bovine endometrium during the oestrous cycle and early pregnancy. Reproduction
CR
2006;131:573-82.
[114] Bateman RL, Rauh D, Tavshanjian B, Shokat KM. Human carbonyl reductase 1 is an S-
US
nitrosoglutathione reductase. J Biol Chem 2008;283:35756-62.
AN
[115] Matsuo M, Ensor CM, Tai HH. Cloning and expression of the cDNA for mouse NAD(+)dependent 15-hydroxyprostaglandin dehydrogenase. Biochim Biophys Acta 1996;1309:21-4.
M
[116] Gonzalez B, Sapra A, Rivera H, Kaplan WD, Yam B, Forrest GL. Cloning and expression
ED
of the cDNA encoding rabbit liver carbonyl reductase. Gene 1995;154:297-8. [117] Zhang H, Matsuo M, Zhou H, Ensor CM, Tai HH. Cloning and expression of the cDNA for
PT
rat NAD+-dependent 15-hydroxyprostaglandin dehydrogenase. Gene 1997;188:41-4.
CE
[118] Wermuth B, Mader-Heinemann G, Ernst E. Cloning and expression of carbonyl reductase from rat testis. Eur J Biochem 1995;228:473-9.
carbonyl
AC
[119] Ghosh D, Sawicki M, Pletnev V, Erman M, Ohno S, Nakajin S, Duax WL. Porcine reductase.
structural
basis
for
a
functional
monomer
in
short
chain
dehydrogenases/reductases. J Biol Chem 2001;276:18457-63. [120] Tai HH, Ensor CM, Tong M, Zhou H, Yan F. Prostaglandin catabolizing enzymes. Prostaglandins Other Lipid Mediat 2002;68-69:483-93. [121] Cho H, Hamza A, Zhan CG, Tai HH. Key NAD+-binding residues in human 15-
44
ACCEPTED MANUSCRIPT hydroxyprostaglandin dehydrogenase. Arch Biochem Biophys 2005;433:447-53. [122] Urade Y, Fujimoto N, Ujihara M, Hayaishi O. Biochemical and immunological characterization of rat spleen prostaglandin D synthetase. J Biol Chem 1987;262:3820-5. [123] Urade Y, Watanabe K, Hayaishi O. Prostaglandin D, E, and F synthases. J Lipid Mediat
T
Cell Signal 1995;12:257-73.
IP
[124] Inoue T, Irikura D, Okazaki N, Kinugasa S, Matsumura H, Uodome N, Yamamoto M,
CR
Kumasaka T, Miyano M, Kai Y, Urade Y. Mechanism of metal activation of human hematopoietic prostaglandin D synthase. Nat Struct Biol 2003;10:291-6.
US
[125] Kanaoka Y, Fujimori K, Kikuno R, Sakaguchi Y, Urade Y, Hayaishi O. Structure and
AN
chromosomal localization of human and mouse genes for hematopoietic prostaglandin D synthase. Conservation of the ancestral genomic structure of sigma-class glutathione S-
M
transferase. Eur J Biochem 2000;267:3315-22.
ED
[126] Pinzar E, Miyano M, Kanaoka Y, Urade Y, Hayaishi O. Structural basis of hematopoietic
2000;275:31239-44.
PT
prostaglandin D synthase activity elucidated by site-directed mutagenesis. J Biol Chem
CE
[127] Shimizu T, Yamamoto S, Hayaishi O. Purification and properties of prostaglandin D synthetase from rat brain. J Biol Chem 1979;254:5222-8.
AC
[128] Hoffmann A, Conradt HS, Gross G, Nimtz M, Lottspeich F, Wurster U. Purification and chemical characterization of beta-trace protein from human cerebrospinal fluid: its identification as prostaglandin D synthase. J Neurochem 1993;61:451-6. [129] Watanabe K, Urade Y, Mader M, Murphy C, Hayaishi O. Identification of beta-trace as prostaglandin D synthase. Biochem Biophys Res Commun 1994;203:1110-6. [130] Gerena RL, Irikura D, Urade Y, Eguchi N, Chapman DA, Killian GJ. Identification of a
45
ACCEPTED MANUSCRIPT fertility-associated protein in bull seminal plasma as lipocalin-type prostaglandin D synthase. Biol Reprod 1998;58:826-33. [131] Zhou Y, Shaw N, Li Y, Zhao Y, Zhang R, Liu ZJ. Structure-function analysis of human lprostaglandin D synthase bound with fatty acid molecules. FASEB J 2010;24:4668-77.
T
[132] Fujimori K, Inui T, Uodome N, Kadoyama K, Aritake K, Urade Y. Zebrafish and chicken
IP
lipocalin-type prostaglandin D synthase homologues: Conservation of mammalian gene structure
CR
and binding ability for lipophilic molecules, and difference in expression profile and enzyme activity. Gene 2006;375:14-25.
US
[133] Kumasaka T, Aritake K, Ago H, Irikura D, Tsurumura T, Yamamoto M, Miyano M, Urade
AN
Y, Hayaishi O. Structural basis of the catalytic mechanism operating in open-closed conformers of lipocalin type prostaglandin D synthase. J Biol Chem 2009;284:22344-52.
M
[134] Madore E, Harvey N, Parent J, Chapdelaine P, Arosh JA, Fortier MA. An aldose reductase
ED
with 20α-hydroxysteroid dehydrogenase activity is most likely the enzyme responsible for the production of prostaglandin F2α in the bovine endometrium. J Biol Chem 2003;278:11205-12.
PT
[135] Kabututu Z, Manin M, Pointud JC, Maruyama T, Nagata N, Lambert S, Lefrancois-
CE
Martinez AM, Martinez A, Urade Y. Prostaglandin F2α synthase activities of aldo-keto reductase 1B1, 1B3 and 1B7. J Biochem 2009;145:161-8.
AC
[136] Kabututu Z, Martin SK, Nozaki T, Kawazu S, Okada T, Munday CJ, Duszenko M, Lazarus M, Thuita LW, Urade Y, Kubata BK. Prostaglandin production from arachidonic acid and evidence for a 9,11-endoperoxide prostaglandin H2 reductase in Leishmania. Int J Parasitol 2003;33:221-8. [137] Moriuchi H, Koda N, Okuda-Ashitaka E, Daiyasu H, Ogasawara K, Toh H, Ito S, Woodward
DF,
Watanabe
K.
Molecular
46
characterization
of
a
novel
type
of
ACCEPTED MANUSCRIPT prostamide/prostaglandin F synthase, belonging to the thioredoxin-like superfamily. J Biol Chem 2008;283:792-801. [138] Kubata BK, Duszenko M, Kabututu Z, Rawer M, Szallies A, Fujimori K, Inui T, Nozaki T, Yamashita K, Horii T, Urade Y, Hayaishi O. Identification of a novel prostaglandin F2α synthase
T
in Trypanosoma brucei. J Exp Med 2000;192:1327-38.
IP
[139] Kubata BK, Kabututu Z, Nozaki T, Munday CJ, Fukuzumi S, Ohkubo K, Lazarus M,
CR
Maruyama T, Martin SK, Duszenko M, Urade Y. A key role for old yellow enzyme in the
US
metabolism of drugs by Trypanosoma cruzi. J Exp Med 2002;196:1241-51. [140] Kuchinke W, Barski O, Watanabe K, Hayaishi O. A lung type prostaglandin F synthase is
AN
expressed in bovine liver: cDNA sequence and expression in E. coli. Biochem Biophys Res Commun 1992;183:1238-46.
M
[141] Suzuki-Yamamoto T, Nishizawa M, Fukui M, Okuda-Ashitaka E, Nakajima T, Ito S,
FEBS Lett 1999;462:335-40.
ED
Watanabe K. cDNA cloning, expression and characterization of human prostaglandin F synthase.
PT
[142] Schieber A, Frank RW, Ghisla S. Purification and properties of prostaglandin 9-
CE
ketoreductase from pig and human kidney. Identity with human carbonyl reductase. Eur J Biochem 1992;206:491-502.
AC
[143] Komoto J, Yamada T, Watanabe K, Takusagawa F. Crystal structure of human prostaglandin F synthase (AKR1C3). Biochemistry 2004;43:2188-98. [144] Schlegel BP, Jez JM, Penning TM. Mutagenesis of 3α-hydroxysteroid dehydrogenase reveals a "push-pull" mechanism for proton transfer in aldo-keto reductases. Biochemistry 1998;37:3538-48. [145] Matsuura K, Shiraishi H, Hara A, Sato K, Deyashiki Y, Ninomiya M, Sakai S.
47
ACCEPTED MANUSCRIPT Identification of a principal mRNA species for human 3α-hydroxysteroid dehydrogenase isoform (AKR1C3) that exhibits high prostaglandin D2 11-ketoreductase activity. J Biochem 1998;124:940-6. [146] Hara S, Miyata A, Yokoyama C, Inoue H, Brugger R, Lottspeich F, Ullrich V, Tanabe T.
T
Isolation and molecular cloning of prostacyclin synthase from bovine endothelial cells. J Biol
IP
Chem 1994;269:19897-903.
CR
[147] Cho SA, Rohn-Glowacki KJ, Jarrar YB, Yi M, Kim WY, Shin JG, Lee SJ. Analysis of genetic polymorphism and biochemical characterization of a functionally decreased variant in
US
prostacyclin synthase gene (CYP8A1) in humans. Arch Biochem Biophys 2015;569:10-8.
AN
[148] Choudhary D, Jansson I, Schenkman JB, Sarfarazi M, Stoilov I. Comparative expression profiling of 40 mouse cytochrome P450 genes in embryonic and adult tissues. Arch Biochem
M
Biophys 2003;414:91-100.
ED
[149] Gillio-Meina C, Phang SH, Mather JP, Knight BS, Kennedy TG. Expression patterns and role of prostaglandin-endoperoxide synthases, prostaglandin E synthases, prostacyclin synthase,
in
rat
2009;137:537-52.
endometrium
during
artificially-induced
decidualization.
Reproduction
CE
alpha
PT
prostacyclin receptor, peroxisome proliferator-activated receptor delta and retinoid x receptor
AC
[150] Hecker M, Ullrich V. On the mechanism of prostacyclin and thromboxane A2 biosynthesis. J Biol Chem 1989;264:141-50. [151] Li YC, Chiang CW, Yeh HC, Hsu PY, Whitby FG, Wang LH, Chan NL. Structures of prostacyclin synthase and its complexes with substrate analog and inhibitor reveal a ligandspecific heme conformation change. J Biol Chem 2008;283:2917-26. [152] Wang LH, Kulmacz RJ. Thromboxane synthase: structure and function of protein and
48
ACCEPTED MANUSCRIPT gene. Prostaglandins Other Lipid Mediat 2002;68-69:409-22. [153] Sadowitz PD, Setty BN, Stuart M. The platelet cyclooxygenase metabolite 12-L-hydroxy5, 8, 10-hepta-decatrienoic acid (HHT) may modulate primary hemostasis by stimulating prostacyclin production. Prostaglandins 1987;34:749-63.
T
[154] Hsu PY, Tsai AL, Kulmacz RJ, Wang LH. Expression, purification, and spectroscopic
IP
characterization of human thromboxane synthase. J Biol Chem 1999;274:762-9.
CR
[155] Zhang L, Chase MB, Shen RF. Molecular cloning and expression of murine thromboxane synthase. Biochem Biophys Res Commun 1993;194:741-8.
US
[156] Zhang L, Xiao H, Schultz RA, Shen RF. Genomic organization, chromosomal localization,
AN
and expression of the murine thromboxane synthase gene. Genomics 1997;45:519-28. [157] Tone Y, Miyata A, Hara S, Yukawa S, Tanabe T. Abundant expression of thromboxane
M
synthase in rat macrophages. FEBS Lett 1994;340:241-4.
ED
[158] Shen RF, Tai HH. Immunoaffinity purification and characterization of thromboxane synthase from porcine lung. J Biol Chem 1986;261:11592-9.
PT
[159] Ruan KH, Milfeld K, Kulmacz RJ, Wu KK. Comparison of the construction of a 3-D
CE
model for human thromboxane synthase using P450cam and BM-3 as templates: implications for the substrate binding pocket. Protein Eng 1994;7:1345-51.
AC
[160] Hsu PY, Tsai AL, Wang LH. Identification of thromboxane synthase amino acid residues involved in heme-propionate binding. Arch Biochem Biophys 2000;383:119-27. [161] Corey EJ, Schaaf TK, Huber W, Koelliker U, Weinshenker NM. Total Synthesis of Prostaglandins F2α and E2 as the Naturally Occuring Forms. J Am Chem Soc 1970;92:397-398. [162] Capper EA, Marshall LA. Mammalian phospholipases A2: mediators of inflammation, proliferation and apoptosis. Prog Lipid Res 2001;40:167-97.
49
ACCEPTED MANUSCRIPT [163] Jakobsson PJ, Thoren S, Morgenstern R, Samuelsson B. Identification of human prostaglandin E synthase: a microsomal, glutathione-dependent, inducible enzyme, constituting a potential novel drug target. Proc Natl Acad Sci U S A 1999;96:7220-5. [164] Chan BS, Endo S, Kanai N, Schuster VL. Identification of lactate as a driving force for
T
prostanoid transport by prostaglandin transporter PGT. Am J Physiol Renal Physiol
IP
2002;282:F1097-102.
CR
[165] Schuster VL, Chi Y, Lu R. The Prostaglandin Transporter: Eicosanoid Reuptake, Control of Signaling, and Development of High-Affinity Inhibitors as Drug Candidates. Trans Am Clin
US
Climatol Assoc 2015;126:248-57.
AN
[166] Kanai N, Lu R, Satriano JA, Bao Y, Wolkoff AW, Schuster VL. Identification and characterization of a prostaglandin transporter. Science 1995;268:866-9.
M
[167] Pucci ML, Bao Y, Chan B, Itoh S, Lu R, Copeland NG, Gilbert DJ, Jenkins NA, Schuster
ED
VL. Cloning of mouse prostaglandin transporter PGT cDNA: species-specific substrate affinities. Am J Physiol 1999;277:R734-41.
PT
[168] Lu R, Schuster VL. Molecular cloning of the gene for the human prostaglandin transporter
CE
hPGT: gene organization, promoter activity, and chromosomal localization. Biochem Biophys Res Commun 1998;246:805-12.
AC
[169] Lu R, Kanai N, Bao Y, Schuster VL. Cloning, in vitro expression, and tissue distribution of a human prostaglandin transporter cDNA(hPGT). J Clin Invest 1996;98:1142-9. [170] Miyazaki H, Sekine T, Endou H. The multispecific organic anion transporter family: properties and pharmacological significance. Trends Pharmacol Sci 2004;25:654-62. [171] Brash AR, Baertschi SW, Ingram CD, Harris TM. On non-cyclooxygenase prostaglandin synthesis in the sea whip coral, Plexaura homomalla: an 8(R)-lipoxygenase pathway leads to
50
ACCEPTED MANUSCRIPT formation of an alpha-ketol and a Racemic prostanoid. J Biol Chem 1987;262:15829-39. [172] Koljak R, Boutaud O, Shieh BH, Samel N, Brash AR. Identification of a naturally occurring peroxidase-lipoxygenase fusion protein. Science 1997;277:1994-6. [173] Weinheimer AJ, Spraggins RL. The occurrence of two new prostaglandin derivatives (15-
T
epi-PGA2 and its acetate, methyl ester) in the gorgonian Plexaura homomalla chemistry of
IP
coelenterates. XV. Tetrahedron Lett 1969;5185-8.
CR
[174] Schneider WP, Hamilton RD, Rhuland LE. Occurrence of esters of (15S)-prostaglandin A2 and E2 in coral. J Am Chem Soc 1972;94:2122-3.
US
[175] Light RJ, Samuelsson B. Identification of prostaglandins in the gorgonian, Plexaura
AN
homomalla. Eur J Biochem 1972;28:232-40.
[176] Varvas K, Järving I, Koljak R, Vahemets A, Pehk T, Müürisepp A-M, Lille Ü, Samel N. In
M
vitro biosynthesis of prostaglandins in the White Sea soft coral Gersemia fruticosa: Formation of
ED
optically active PGD2, PGE2, PGF2α and 15-keto-PGF2α from arachidonic acid. Tetrahedron Lett 1993;34:3643-3646.
PT
[177] Varvas K, Koljak R, Järving I, Pehk T, Samel N. Endoperoxide pathway in prostaglandin
CE
biosynthesis in the soft coral Gersemia fruticosa. Tetrahedron Lett 1994;35:8267-8270. [178] Parve O, Jarving I, Martin I, Metsala A, Vallikivi I, Aidnik M, Pehk T, Samel N. Lipase-
AC
catalysed acylation of prostanoids. Bioorg Med Chem Lett 1999;9:1853-8. [179] Sajiki J. Acid Treatment Increased Leukotriene B4 in The Red Alga, Gracilaria asiatica (= verrucosa). Fisheries Sci 1999;65:914-918. [180] Imbs AB, Vologodskaya AV, Nevshupova NV, Khotimchenko SV, Titlyanov EA. Response of prostaglandin content in the red alga Gracilaria verrucosa to season and solar irradiance. Phytochemistry 2001;58:1067-72.
51
ACCEPTED MANUSCRIPT [181] Dang TH, Lee HJ, Yoo ES, Hong J, Choi JS, Jung JH. The occurrence of 15-ketoprostaglandins in the red alga Gracilaria verrucosa. Arch Pharm Res 2010;33:1325-9. [182] Gregson RP, Marwood JF, Quinn RJ. The occurrence of prostaglandins PGE2 and PGF2α in a plant-the red alga Gracilaria lichenoides. Tetrahedron Lett 1979;20:4505-4506.
T
[183] Hsu BY, Tsao CY, Chiou TK, Hwang PA, Hwang DF. HPLC determination for
IP
prostaglandins from seaweed Gracilaria gigas. Food Control 2007;18:639-645.
CR
[184] Nylund GM, Weinberger F, Rempt M, Pohnert G. Metabolomic assessment of induced and activated chemical defence in the invasive red alga Gracilaria vermiculophylla. PLoS One
US
2011;6:e29359.
AN
[185] Rempt M, Weinberger F, Grosser K, Pohnert G. Conserved and species-specific oxylipin pathways in the wound-activated chemical defense of the noninvasive red alga Gracilaria
M
chilensis and the invasive Gracilaria vermiculophylla. Beilstein J Org Chem 2012;8:283-9.
ED
[186] Kanamoto H, Takemura M, Ohyama K. Identification of a cyclooxygenase gene from the red alga Gracilaria vermiculophylla and bioconversion of arachidonic acid to PGF2α in
PT
engineered Escherichia coli. Appl Microbiol Biotechnol 2011;91:1121-9.
CE
[187] Guder JC, Buchhaupt M, Huth I, Hannappel A, Ferreiros N, Geisslinger G, Schrader J. Biotechnological approach towards a highly efficient production of natural prostaglandins.
AC
Biotechnol Lett 2014;36:2193-8. [188] Noverr MC, Phare SM, Toews GB, Coffey MJ, Huffnagle GB. Pathogenic yeasts Cryptococcus neoformans and Candida albicans produce immunomodulatory prostaglandins. Infect Immun 2001;69:2957-63. [189] Grozer Z, Toth A, Toth R, Kecskemeti A, Vagvolgyi C, Nosanchuk JD, Szekeres A, Gacser A. Candida parapsilosis produces prostaglandins from exogenous arachidonic acid and OLE2 is
52
ACCEPTED MANUSCRIPT not required for their synthesis. Virulence 2015;6:85-92. [190] Erb-Downward JR, Noverr MC. Characterization of prostaglandin E2 production by Candida albicans. Infect Immun 2007;75:3498-505. [191] Erb-Downward JR, Noggle RM, Williamson PR, Huffnagle GB. The role of laccase in
T
prostaglandin production by Cryptococcus neoformans. Mol Microbiol 2008;68:1428-37.
IP
[192] Broadway N. Recombinant protein expression: vector-host systems. Mater Methods
CR
2012;2:123.
[193] Kukk K, Jarving R, Samel N. Purification and characterization of the recombinant human
US
prostaglandin H synthase-2 expressed in Pichia pastoris. Protein Expr Purif 2012;83:182-9.
AN
[194] Macauley-Patrick S, Fazenda ML, McNeil B, Harvey LM. Heterologous protein production using the Pichia pastoris expression system. Yeast 2005;22:249-270.
M
[195] Kukk K, Samel N. Enhanced expression of human prostaglandin H synthase-2 in the yeast
ED
Pichia pastoris and removal of the C-terminal tag with bovine carboxypeptidase A. J Biotechnol 2016;231:224-31.
PT
[196] Shyue SK, Tsai MJ, Liou JY, Willerson JT, Wu KK. Selective augmentation of prostacyclin
2001;103:2090-5.
CE
production by combined prostacyclin synthase and cyclooxygenase-1 gene transfer. Circulation
AC
[197] Kim WI, Choi KA, Do HS, Yu YG. Expression and purification of human mPGES-1 in E. coli and identification of inhibitory compounds from a drug-library. BMB Rep 2008;41:808-13. [198] Mohamed ME, Lazarus CM. Prostanoid production in Saccharomyces cerevisiae provides a novel assay for nonsteroidal anti-inflammatory drugs. FEMS Yeast Res 2009;9:420-7. [199] Gong Y, Wan X, Jiang M, Hu C, Hu H, Huang F. Metabolic engineering of microorganisms to produce omega-3 very long-chain polyunsaturated fatty acids. Prog Lipid Res 2014;56:19-35.
53
ACCEPTED MANUSCRIPT [200] Tavares S, Grotkjaer T, Obsen T, Haslam RP, Napier JA, Gunnarsson N. Metabolic engineering of Saccharomyces cerevisiae for production of eicosapentaenoic acid, using a novel delta-5-Desaturase from Paramecium tetraurelia. Appl Environ Microbiol 2011;77:1854-61. [201] Sakuradani E, Ando A, Shimizu S, Ogawa J. Metabolic engineering for the production of
T
polyunsaturated fatty acids by oleaginous fungus Mortierella alpina 1S-4. J Biosci Bioeng
IP
2013;116:417-22.
CR
[202] Hao G, Chen H, Gu Z, Zhang H, Chen W, Chen YQ. Metabolic engineering of Mortierella alpina for arachidonic acid production with glycerol as carbon source. Microb Cell Fact
US
2015;14:205.
AN
[203] Hao G, Chen H, Gu Z, Zhang H, Chen W, Chen YQ. Metabolic engineering of Mortierella
Environ Microbiol 2016;82:3280-8.
M
alpina for enhanced arachidonic acid production through the NADPH-supplying strategy. Appl
ED
[204] Xue Z, Sharpe PL, Hong SP, Yadav NS, Xie D, Short DR, Damude HG, Rupert RA, Seip JE, Wang J, Pollak DW, Bostick MW, Bosak MD, Macool DJ, Hollerbach DH, Zhang H, Arcilla
PT
DM, Bledsoe SA, Croker K, McCord EF, Tyreus BD, Jackson EN, Zhu Q. Production of omega-
AC
2013;31:734-40.
CE
3 eicosapentaenoic acid by metabolic engineering of Yarrowia lipolytica. Nat Biotechnol
54
ACCEPTED MANUSCRIPT Figure legends
Fig. 1. Nomenclature of PGs. (A) PGs are assigned as the suffix of PG using a letter from A to K based on the position of the substituents on the cyclopentane ring. TXA or TXB is assigned as a
IP
T
six-membered ether-containing ring. R1 and R2 indicate the carbon chains. (B) PGX1, PGX2 and
CR
PGX3 are assigned as the subscript number of PGX using the number of double bonds in the carbon chains, and they are derived from DGLA, AA, and EPA, respectively. ‘X’ indicate
US
several types of cyclopentane rings. R1 and R2 show the carboxylic (upper chemical structure)
AN
and hydro(pero)xyl (lower chemical structure) groups, respectively. Fig. 2. Synthesis pathway of diverse PGs from PGH2. PGE2, 15-keto-PGE2, PGD2, PGF2α, PGI2,
M
and TXA2 are formed by PG synthases (solid line). PGA2, PGB2, PGC2, PGJ2,
∆12,14
15-deoxy-
ED
PGJ2, 6-keto-PGF1α, and TXB2 are formed by non-enzymatic reactions (dotted line).
PT
Fig. 3. Proposed reaction mechanisms and 3D-structures of active sites in PG synthases. (A) PGHS (PDB No. 1U67). (B) PGES (PDB No. 4AL1). (C) 15-HPGD (PDB No. 2GDZ). (D) H-
CE
PGDS (PDB No. 1PD2). (E) L-PGDS (PDB No. 3O19). (F) PGFS-1 (PDB No. 1VBJ). (G)
AC
PGFS-2 (PDB No. 1RY0). (H) PGIS (PDB No. 2IAG). (I) TXAS (Molecular model). Internal molecules (turquoise blue) indicate ligands. Red color indicates catalytic residues. Purple color indicates residues involved in the abstraction of electron donor. Gold and gray colors indicate residues involved in the cyclization for PGH2 and NSAIDs-binding site of PGHS, respectively. Green color indicates residues involved in the interaction with co-factors. Dark-blue color indicates residues involved in the formation of hydrogen bonds. Pink color indicates residues involved in the formation of catalytic triad or tetrad. Blue color indicates substrate-binding site
55
ACCEPTED MANUSCRIPT residues. Orange color indicates residues involved in the interaction with metal. Lavender-purple color indicates residues involved in the activation of thiol group. Dark-green color indicates residues involved in release of PGD2. Sky-blue color indicates residues involved in interaction with heme. 3D-structures of PG synthases are redrawn using Discovery Studio 4.0 (Accerlys,
IP
T
San Diego, CA, USA) based on their crystal structures.
CR
Fig. 4. Mammalian, algal, coral, and fungal biosynthesis pathways of PGs derived from AA released from phospholipids by phospholipase A2. Solid lines indicate experimentally confirmed
US
pathways, and dotted lines indicate putative pathways. NE, non-enzymatic reactions.
AN
Fig. 5. Proposed metabolically engineered pathway for synthesis of C20 unsaturated fatty acid. PGs can be synthesized from three types of substrates including DGLA (blue), AA (red), and
M
EPA (purple) by PG-converting enzymes. LA, linoleic acid (C18:2∆9Z, 12Z); ALA, α-linolenic acid
ED
(C18:3∆9Z, 12Z, 15Z); EDA, eicosadienoic acid (C20:2∆11Z, 14Z); ETrA, eicosatrienoic acid (C20:3∆11Z, ); DGLA, dihomo-γ-linolenic acid (C20:3∆8Z,11Z,14Z); ETA, eicosatetraenoic acid (C20:4∆8Z,
14Z, 17Z
); AA, arachidonic acid (C20:4∆5Z, 8Z, 11Z, 14Z); EPA, eicosapentaenoic acid (C20:5∆5Z, 8Z,
PT
11Z, 14Z, 17Z
11Z, 14Z, 17Z
AC
CE
)
56
ACCEPTED MANUSCRIPT
US
CR
IP
T
A
AC
CE
PT
ED
M
AN
B
Fig. 1
57
AC
CE
PT
ED
M
AN
US
CR
IP
T
ACCEPTED MANUSCRIPT
Fig. 2
58
CR IP T AC
CE
PT
ED
M AN
US
A
Fig. 3-continued
59
CR IP T US AC
CE
PT
ED
M AN
B
Fig. 3-continued
60
CR IP T AC
CE
PT
ED
M AN
US
C
Fig. 3-continued
61
CR IP T AC
CE
PT
ED
M AN
US
D
Fig. 3-continued
62
CR IP T AC
CE
PT
ED
M AN
US
E
Fig. 3-continued
63
CR IP T AC
CE
PT
ED
M AN
US
F
Fig. 3-continued 64
CR IP T AC
CE
PT
ED
M AN
US
G
Fig. 3-continued 65
CR IP T AC
CE
PT
ED
M AN
US
H
Fig. 3-continued 66
ED
PT
CE
AC
CR IP T
US
M AN
I
Fig. 3
67
AC
CE
PT
ED
M
AN
US
CR
IP
T
ACCEPTED MANUSCRIPT
Fig. 4
68
Fig. 5
69
ED
PT
CE
AC
CR IP T
US
M AN
ACCEPTED MANUSCRIPT Table 1. Functions of prostaglandins. Structure
Receptor
Functions
Ref.
Prostaglandin H2 (PGH2)
−
Precursor of other prostaglandins
[3]
Prostaglandin E2 (PGE2)
EP1, EP2, EP3, EP4
Pain response, Maturation for ovulation, Fertilization
[3, 15]
15-Ketoprostaglandin E2 (15-Keto-PGE2)
PPAR-γ
Agonist, Induces adipogenesis
Prostaglandin D2 (PGD2)
DP1, DP2
Allergic asthma, Chemotaxis
Prostaglandin F2α (PGF2α)
PGF
CR
US
[40]
[30, 31]
[32, 33]
IP1, IP2
Vasodilation, Declumping
[34, 35]
TPα , TPβ
Vasoconstriction, Platelet aggregation
[38, 39]
M
AN
Contraction, Parturition,
AC
CE
PT
ED
Prostaglandin I2 (PGI2)
Thromboxane A2 (TXA2)
IP
T
Prostaglandin
70
CR IP T
Table 2. Biochemical properties of prostaglandin synthases.
PGHS-1
Bos taurus Danio rerio Homo sapiens Ovis aries (POX) Mus musculus Rattus norvegicus Gracilaria vermiculophylla Bos taurus Caprella sp. Cavia porcellus Danio rerio Equus caballus Gallus gallus Gammarus sp. Homo sapiens Mus musculus Neovison vison Oryctolagus cuniculus Ovis aries Rattus norvegicus Gersemia fruticosa Plexaura homomalla Bombyx mori Danio rerio Homo sapiens
Substrate
AA − AA 15-HPETE AA AA AA AA AA AA − AA AA AA AA AA AA AA AA AA AA AA PGH2 PGH2 PGH2
PGES
AC
CE
PT
ED
PGHS-2
Typical organism
cPGES
mPGES-1
mPGES-2
Km
kcat
(µM )
(s )
Temp. o ( C)
pH
Mw (Da)
Quaternary structure
Ref.
− − 37 37 37 − 25 − 25 − − − − 25 25 37 − − − − 25 25
− − 8.0 8.0 8.0 − 8.0 − 8.0 − − − − 8.0 7.2 – 8.0 8.0 − − − − 8.0 8.0
− − Dimer Dimer Dimer Dimer Tetramer − − − − − Dimer − Dimer Dimer − − Dimer − − −
[79] [91] [60] [86] [82] [88] [94] [205] [92] [206] [91] [80] [90] [92] [81] [83] [84] [85] [87] [89] [23] [93]
25 −
8.0 −
Monomer −
[100] [101]
8.0
70,000 68,963 73,000 70,000 70,000 70,000 63,500 72,000 68,000 69,000 68,673 69,000 70,000 68,000 70,000 70,000 69,000 69,000 72,000 72,000 68,000 68,000 24,000 17,149 26,000
Monomer
[42]
− − 8.0
16,000 16,458 17,500
− − Trimer
Accession no.
Specific activity (µmol/min/mg)
O62664 Q8JH44 P23219 P05979 P22437 Q63921 I6VVK9 O62698 D2W902 P70682 Q8JH43 O19183 P27607 D2W903 P35354 Q05769 O62725 O02768 P79208 P35355 Q9GPF4 Q962I8 Q5CCJ4 Q5IHX6 Q15185
− − 19 34 0.3 − 124 − − − − − − − 12.2 − − − 30.8 − − − 0.07 − 1.9
− − 5.1 42 − − 21 − − − − − − − 8.7 5.1 − − 2.1 − − − − − 14
120 − − 92 − − − − − − − − 27 − − − − − − − − 0.8
24
− − 170
− − 160
− − 50
− − 37
US
PGHS
Subtype
M AN
Enzyme
−1
−1
− −
Bos taurus Danio rerio Homo sapiens
− PGH2 PGH2
Q95L14 Q5IHX7 O14684
Mus musculus
PGH2
Q9JM51
−
130
10
24
8.0
17,000
−
[104] [101] [97] [103]
Rattus norvegicus
PGH2
Q9JHF3
−
−
−
−
7.0
17,000
−
[102]
Sus scrofa Bos taurus
− PGH2
Q2TJZ7 Q66LN0
− 0.83
− 24
− 0.43
− 24
− 6.5
17,300 33,000
− Dimer
[108]
71
[107]
15-HPGD-2
−
−
−
−
−
41,914
−
[109]
Q9N0A4 Q8BWM0 Q309F3
3.3 − 3.3
28 − −
1.8 − −
24 − 25
6.5 − 9.0
33,107 44,000 29,000
Dimer − Dimer
[109] [110] [113]
Homo sapiens
PGE2
P15428
2.8
3.4
50
37
7.5
29,000
Dimer
[112]
Mus musculus Rattus norvegicus
−
− −
− −
− −
− 37
− 9.0
28,775 29,000
Dimer Dimer
[115] [117]
P16152
−
309
P48758 P47844 P47727
− − −
− − 0.0002
− PGH2
Q28960 O60760
− 30
− 200
PGH2
Q9JHF7
28
200
−
25
8.0
23,226
Dimer
[125]
Rattus norvegicus
PGH2
O35543
33
200
−
25
8.0
23.297
Dimer
[125]
Schistosoma mansoni Bos taurus
PGH2 PGH2
P09792 O02853
1 0.005
0.31 −
− −
25 −
7.4 −
28,000 26,000
− Monomer
[22] [130]
Danio rerio
PGH2
Q8QGV4
−
−
−
−
−
20,875
−
[101]
Homo sapiens
PGH2
P41222
9.3
14
26
25
8.0
29,000
Monomer
[131]
Gallus gallus
PGH2
Q8QFM7
12
−
−
25
8.0
21,000
Monomer
[132]
Mus musculus
PGH2
O09114
434
−
−
25
8.0
21,000
Monomer
[132]
Bos taurus Homo sapiens Leishmania major
PGH2 PGH2 PGH2
P16116 P15121 P22045
0.024 0.026 0.27
7.1 1.9 15
0.014 0.016 0.14
25 37 37
7.5 7.0 7.0
36,000 36,000 34,000
− Monomer −
[134] [135] [136]
Mus musculus
Sus scrofa
PGH2 PGH2 PGH2 PGH2
Q9DB60 P45376 P21300 A9CQL8
0.69 0.053 0.044 0.69
7.6 9.3 3.8 7.0
0.25 0.032 0.026 0.25
24 37 37 24
7.0 7.0 7.0 7.0
21,669 36,000 36,000 20,000
− Monomer Monomer Dimer
[137] [135] [135] [137]
Q2TJA5 Q9GV41
− 2.0
− 1.3
− 1.30
− 37
− 7.0
36,000 33,000
− −
[107] [138]
Sus scrofa Homo sapiens
PGFS-1
AC
PGFS
CE
L-PGDS
PT
Mus musculus
ED
H-PGDS
PGIS
+
NAD PGE2
Q8VCC1 O08699
− − PGE2
Homo sapiens Mus musculus Oryctolagus cuniculus Rattus norvegicus
PGDS
CR IP T
Q9H7Z7
PGH2 − PGE2
US
15-HPGD-1
PGH2
Macaca fascicularis Mus musculus Bos taurus
M AN
15-HPGD
Homo sapiens
25
37
8.0
30,000
Monomer
[114, 207]
− − 0.03
− − 30
− − 7.0
30,000 30,000 30,000
− − Monomer
[208] [116] [118]
− −
45 25
5.5 8.0
31,000 23,343
Monomer Dimer
[119] [125]
Trypanosoma brucei
− PGH2
Trypanosoma cruzi
PGH2
Q8I6L9
0.77
5.0
0.54
37
7.0
42,000
−
[139]
PGFS-2
Bos taurus Homo sapiens
PGD2 PGD2
P52897 P42330
− 2.0
− 3.4
− 1.2
− 37
− 10.0
37,000 36,000
− −
[140] [141]
PGFS-3
Sus scrofa
PGE2
Q28960
0.02
0.16
−
25
6.5
32,000
Monomer
[142]
Bos taurus
PGH2
Q29626
2.0
9.0
2.45
24
7.4
52,000
−
[146]
Danio rerio
PGH2
A9LLA5
−
−
−
−
−
55,240
−
[101]
PGIS
72
− − PGH2
CR IP T
Mus musculus Rattus norvegicus Sus scrofa
9.5 − − −
P24557
12
20
0.02
23
7.5
56,000
Monomer
[154]
P36423 P49430 P47787
− − 0.23
− − 12
− − −
− − 30
− − 7.5
58,220 60,000 60,000
− − −
[155, 156] [157] [158]
US
PGH2
534 − − −
M AN
Homo sapiens
Q16647 O35074 Q62969 Q6TGT4
CE
PT
ED
TXAS
U46619 − − PGH2
AC
TXAS
Homo sapiens Mus musculus Rattus norvegicus Danio rerio
73
− − − −
23 − − −
7.5 − − −
56,000 57,000 56,500 62,790
Monomer − Monomer −
[147] [148] [149] [101]
CR IP T
Table 3. Structural information of prostaglandin synthases. PDB no.
Co-factor
Catalytic residue
PGHS
1U67
Heme
Tyr385
Substrate-binding residues
US
Enzyme
Residue function
Arg120
Opening the active site
207
388
Heme liganding
348
533
Hydrogen abstraction
349
387
Cyclization
49
126
L-PGDS
PGFS-1
PGFS-2
PGFS-3 PGIS TXAS
3O19
Ser
NAD+ or NADP+
ED
1PD2
GSH
2+
GSH and Mg
PT
H-PGDS
2GDZ
127
−
CE
15-HPGD
4AL1
1VBJ
AC
PGES
M AN
His , His
1RY0
1N5D
2IAG −
NADPH
NADPH
Ser138
Tyr , Gly
Val
, Trp
Asp , Arg
Proton abstraction
Arg73, Asn17, Glu77, His113, Tyr117, Arg126
GSH coordination
Tyr151, Lys155
Formation of catalytic triad
Gln
148
Formation of hydrogen bonds
11
74
91
182
Thr , Ile , Asn , Cys , Val 8
Tyr
14
Arg , Trp
104
96
96
97
Lys112, Cys156, Lys198 Cys
45
67
54
111
81
47
77
Trp , His
Tyr 117
Interaction with Mg2+ Substrate binding
Interaction with cofactor
52
55
Cofactor binding site
Involved in release of PGD2
Asp , Lys
His
, Thr
Activation of the thiol group of Cys65
Ser , Thr , Ser
110
188
GSH transfer
Asp , Asp , Asp 65
186
Formation of catalytic tetrad
50
84
Tyr , His
Asp , Lys
194
106
Interaction with cofactor Formation of catalytic tetrad
NADPH and GSH Heme Heme
Tyr
441
Cys
480
Cys
Asp
, Gln
140
Interaction with cofactor
447
Ala
Heme liganding
110
413
133
137
478
Asn , Arg , Arg Trp
, Arg
Arg86, Phe127, Met237, Leu521
74
Interaction with A−ring of heme Interaction with D−ring of heme Stabilization of binding pocket
and
Min-Ju Seo, Deok-Kun Oh PII: DOI: Reference:
S0163-7827(16)30060-1 doi: 10.1016/j.plipres.2017.04.003 JPLR 941
To appear in:
Progress in Lipid Research
Received date: Revised date: Accepted date:
26 December 2016 30 March 2017 1 April 2017
Please cite this article as: Min-Ju Seo, Deok-Kun Oh , Prostaglandin synthases: Molecular characterization and involvement in prostaglandin biosynthesis. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Jplr(2017), doi: 10.1016/j.plipres.2017.04.003
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Prostaglandin synthases: Molecular characterization and
T
involvement in prostaglandin biosynthesis
CR
IP
Min-Ju Seo, Deok-Kun Oh*
US
Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of
PT
ED
M
AN
Korea
CE
* Corresponding author at: Department of Bioscience and Biotechnology, Konkuk University,
AC
120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea. E-mail address: [email protected] (D. K. Oh)
1
ACCEPTED MANUSCRIPT Contents Introduction Functions of prostaglandins Prostaglandin synthases 3.1. Prostaglandin G/H synthase 3.1.1. Enzyme properties 3.1.2. Mechanism and active site 3.2. Prostaglandin E synthase 3.2.1. Properties of cPGES 3.2.2. Properties of mPGESs 3.2.2. Mechanism and active site of mPGES-1 3.3. 15-Hydroxyprostaglandin dehydrogenase 3.3.1. Enzyme properties 3.3.2. Mechanism and active site 3.4. Prostaglandin D synthase 3.4.1. H-PGDS 3.4.2. L-PGDS 3.5. Prostaglandin F synthase 3.5.1. PGFS-1 3.5.2. PGFS-2 3.6. Prostaglandin I synthase 3.6.1. Enzyme properties 3.6.2. Mechanism and active site 3.7. Thromboxane A synthase 3.7.1. Enzyme properties 3.7.2. Mechanism and active site 4. Synthesis of prostaglandins 4.1. Chemical synthesis 4.2. Biosynthesis 4.2.1. Mammals 4.2.2. Corals 4.2.3. Florideae 4.2.4. Yeast and fungi 5. Future perspectives 5.1. Microbial expression systems for prostaglandin synthesis 5.2. Metabolic engineering for prostaglandin synthesis 6. Conclusion Reference
AC
CE
PT
ED
M
AN
US
CR
IP
T
1. 2. 3.
2
ACCEPTED MANUSCRIPT Abstract Prostaglandins (PGs) belong to a subclass of eicosanoids and are classified based on the structures of the cyclopentane ring and their number of double bonds in their hydrocarbon structures. PGs are important lipid mediators that are involved in inflammatory response. The
T
biosynthesis of diverse PGs from unsaturated C20 fatty acids containing at least three double
IP
bonds such as dihomo-γ-linoleic acid (20:3∆8Z,11Z,14Z), arachidonic acid (20:4∆5Z,8Z,11Z,14Z), and
CR
eicosapentaenoic acid (20:5∆5Z,8Z,11Z,14Z,17Z) is enables by various PG synthases, including prostaglandin H synthase (PGHS), 15-hydroxyprostaglandin dehydrogenase (15-HPGD), PGES,
US
PGDS, PGFS, PGIS, and thromboxane A synthase (TXAS). This review summarizes the
AN
biochemical properties, reaction mechanism, and active site details of PG synthases. Because PGs are involved in the immune system, an understanding of PG synthases is important in the
M
design of new anti-inflammatory drugs. The biosynthesis of PGs in various organisms, such as
ED
mammals, corals, florideae (a class of red algae), yeast, and fungi, is also introduced. The expression of PG synthases in the microbial systems for the synthesis of PGs is discussed. Now,
PT
the biosynthesis of PGs from glucose or glycerol is possible using metabolically engineered cells
AC
CE
expressing both unsaturated fatty acid-producing enzymes and PG synthases.
3
ACCEPTED MANUSCRIPT Abbreviation
AA, arachidonic acid; AKR, aldo-keto reductase; AOS, allene oxide synthase; CX, carbon numbers; COX, cyclooxygenase; cPGES, cytosolic PGE synthase; cPLA2, cytosolic
T
phospholipase A2; CYP, cytochrome P450; DGLA, dihomo-γ-linolenic acid; DP, prostaglandin
IP
D receptor; EGF-like, epidermal growth factor-like; EP, prostaglandin E receptor; EPA,
CR
eicosapentaenoic acid; ER, endoplasmic reticulum; Fet3, multicopper oxidase homolog; FP, prostaglandin F receptor; GSH, glutathione; GPCRs, G protein-coupled receptors; HETE,
US
hydroxyeicosatetraenoic acid; HEK, human embryonic kidney; HHT, hydroxyheptadecatrienoic
AN
acid; HPETE, hydroperoxyeicosatetraenic acid; HPGD, hydroxyprostaglandin dehydrogenase; H-PGDS, hematopoietic PGD synthase; Hsp, heat shock protein; IP, prostaglandin I receptor;
M
Lac1, laccase encoding gene; LOX, lipoxygenase; L-PGDS, lipocalin PGD synthase; MAPEG,
ED
membrane-associated proteins in eicosanoid and GSH metabolism; Me, methyl ester; mPGES, membrane-bound PGE synthase; Mw, molecular weight; NSAIDs, nonsteroidal anti-
PT
inflammatory drugs; NREM, non-rapid eye movement; Ole2, fatty acid desaturase homolog;
CE
PDB, protein data bank; PG, prostaglandin; PGA, prostaglandin A; PGB, prostaglandin B; PGC, prostaglandin C; PGD, prostaglandin D; PGE, prostaglandin E; PGF, prostaglandin F; PGG,
AC
prostaglandin G; PGH, prostaglandin H; PGI, prostaglandin I; PGJ, prostaglandin J; PGT, PG transporter; PGDS, prostaglandin D synthase; PGES, prostaglandin E synthase; PGFS, prostaglandin F synthase; PGHS, prostaglandin G/H synthase; PGIS, prostaglandin I synthase; POX, peroxidase; PPAR-γ, peroxisome proliferator activated receptor-γ; PUFA, polyunsaturated fatty acid; SDR, short-chain dehydrogenase/reductase; TP, thromboxane A receptor; TXA, thromboxane A; TXB, thromboxane B; TXAS, thromboxane A synthase.
4
ACCEPTED MANUSCRIPT 1. Introduction Polyunsaturated fatty acids (PUFAs), which belong to an important group of membrane lipids, are carboxylic acids containing 18-22 carbons (C18-C22) with double bonds of two or more. PUFAs are classified as n-3 (ω-3) and n-6 (ω-6) families depending on the position of the
T
first double bond at the end of PUFAs [1]. PUFAs can be metabolized into signaling compounds
IP
such as leukotrienes, lipoxins, resolvins, and protectins by enzymes in the lipoxygenase (LOX)
CR
pathway [2]. In another metabolic route, arachidonic acid (AA) is converted to prostaglandins (PGs), including PGH2, PGE2, 15-keto-PGE2, PGD2, PGF2α, PGI2, and thromboxane A2 (TXA2),
US
by enzymes in the cyclooxygenase (COX) pathway.
AN
PGs belong to a subclass of eicosanoids known as prostanoids. They contain C20 atoms, including a cyclopentane (5-carbon) ring. They are important secretory lipid mediators in
M
humans and other animals [3]. PGs have two are divided into two groups: prostacyclopentanes
ED
and thromboxanes. Prostacyclopentanes are classified based on the structures of their cyclopentane rings (denoted using a letter from A to K) and the number of double bonds in their
PT
hydrocarbon structures (denoted using a subscripted number from 1 to 3) [4], whereas
CE
thromboxanes consist of TXA and TXB (Fig. 1). PG was first found in seminal fluid in 1935 [5]. In 1950s, PG was first structurally characterized [6, 7]. PGF2α and PGE2 were totally
AC
synthesized using 20-step chemical reactions by E. J. Corey, who was awarded a Nobel Prize in 1990 [8]. Recently, PGF2α has been chemically synthesized using 7-step reactions [9]. PGs can also be biologically synthesized from dihomo-γ-linolenic acid
(DGLA), AA, and
eicosapentaenoic acid (EPA) by PG synthases using 2- or 3-step reactions. PGs are hormone-like chemical messenger that are involved in a diverse range of biological functions in humans. These include the regulation of the immune system, fever and pain
5
ACCEPTED MANUSCRIPT associated with inflammation, hemostasis, and blood pressure [10]. The biological importance of PGs has led to several review articles on their roles in biology, physiology, immunopathology, and pharmaceutics [10-18]. In mammalian cells, PGs are generated from membrane-released AA in response to cytokine, growth factors, and other pro-inflammatory stimuli, and AA is converted
T
to PGH2 via PGG2 as an intermediate by PGG/H synthase (PGHS) and diverse PGs are
IP
synthesized from PGH2 by other PG synthases, including PGE synthase (PGES), 15-
CR
hydroxyprostaglandin dehydrogenase (15-HPGD), PGD synthase (PGDS), PGF synthase (PGFS), PGI synthase (PGIS), and TXA synthase (TXAS). These mammalian PG synthases
US
convert the unsaturated fatty acids DGLA, AA, and EPA containing three, four, and five double
AN
bonds, respectively, to the PG products PGX1, PGX2, and PGX3 containing one, two, and three double bonds, respectively (Fig. 1). PGs are also found in various other non-mammals, including
M
aves (birds), actinopterygii (ray-finned fishes), kinetoplastida (trypanosomes), trematoda (blood-
ED
flukes), bivalvia (molluscs), malacostracas, corals, florideae (a class of red algae), fungi such as Mucoromycotina, Eurotiomycetes, Sordariomycetes, and Zygomycetes classes, and yeast such as
PT
Saccharomycetes and Tremellomycetes classes [19-25]. However, the biochemical properties of
CE
these non-mammalian enzymes and the biosynthesis of PGs in these organisms have not been reviewed thus far. Among the various organisms, only PG synthases suitable for microbial
AC
expression and applicable for PG biosynthesis are reviewed. This review article summarizes the biochemical properties, reaction mechanisms, and active site details of PG synthases as well as the biosynthesis of PGs in non-mammals. Additionally, the latter sections of this review introduce the application of microbial expression systems and metabolically engineered cells for the synthesis of PGs.
6
ACCEPTED MANUSCRIPT 2. Functions of prostaglandins PGs are produced in cells in response to external stimuli and act as autacoids within tissues via specific cell surface receptors and play a role in activating the inflammatory response [15]. PGs exert their inflammatory effects by binding to G protein-coupled receptors (GPCRs), also known
T
as seven-transmembrane domain receptors [26]. These receptors are involved in two principal
IP
signal transduction pathways: the cAMP and the phosphatidylinositol signaling pathways [27].
CR
PG receptors are divided into five basic types: PGE, PGD, PGF, PGI, and TXA receptors [16, 28]. The existence of diverse receptors indicates that PGs can activate a wide array of signal
US
transduction events in diverse cell types and modulating distinct biological effects (Table 1).
AN
PGE2 mediates cellular processes in pro-inflammatory and anti-inflammatory directions. PGE2 binds to PGE receptors, which exist as EP1, EP2, EP3, and EP4 subtypes, and is involved in pain
M
response, oogenesis, ovulation, fertilization, fever generation, and bone resorption [3, 15]. PGD2
ED
binds to two PGD receptors, DP1 and DP2 subtypes. This compound is involved in the regulation of the central nervous systems, pain non-rapid eye movement sleep (NREM) [29], and plays a
PT
role in chemotaxis and in allergy-induced asthma [30, 31]. PGF2α is an agonist for the PGF
CE
receptor and plays an important role in oogenesis, ovulation, luteolysis, contraction of uterine smooth muscle, and initiation of parturition [32, 33]. PGF2α is also used to induce labor and
AC
further functions as an abortifacient [9]. PGI2 is an agonist for the PGI receptors, IP1 and IP2. PGI2 is a potent vasodilator and an inhibitor of platelet aggregation. PGI2 plays a role in leukocyte adhesion, proliferation of vascular smooth muscle cells [34], and regulation of cardiovascular homeostasis [35]. TXA2, one of the most important prostanoids, can be defined as a lipid mediator that acts a vasoconstrictor, platelet activating agent, and modulates endothelial cell responses [36-39]. The
7
ACCEPTED MANUSCRIPT activity of TXA2 is mediated through two TXA receptors: TPα and TPβ. 15-Keto-PGE2 and ∆12,14
15-deoxy-PGJ2 act as agonist of peroxisome proliferator activated receptor-γ (PPAR-γ)
which inhibits tumor growth [40-42].
T
3. Prostaglandin synthases
IP
In this section, the biochemical properties, reaction mechanisms, and active site details of PG
CR
synthases are summarized. In vivo, AA is converted to PGH2 by PGHS. PGH2 is subsequently converted to a variety of PGs by several types of PG synthases (Fig. 2). PGES convert PGH2 to
US
PGE2, which is also a substrate of the enzyme 15-HPGD in the synthesis of 15-keto-PGE2. PGD2
AN
is synthesized from PGH2 by PGDS. PGF2α is produced from PGH2, PGD2, and PGE2 by three types of PGFS, including PGH 9,11-endoperoxide reductase (PGFS-1), PGD 11-ketoreductase
M
(PGFS-2), and PGE 9-ketoreductase (PGFS-3), respectively. PGE2, PGD2, and PGF2 are
ED
relatively stable in aqueous solution at pH 4.0−9.0, while both PGE2 and PGD2 are dehydrated at above pH 10.0 [43]. PGIS converts PGH2 to PGI2, which is unstable below pH 8.0 (half-life is 3
PT
min at pH 7.4 and 37 °C). The unstable PGI2 is hydrolyzed to a stable product, 6-keto-PGF1α.
CE
TXAS converts PGH2 to TXA2, which has a six-membered ring structure containing bicylic oxane-oxetane group. TXA2 (half-life is 30 s at pH 7.4 and 37 °C) is rapidly hydrolyzed to TXB2.
AC
Thus, the formation of PGI2 and TXA2 can be monitored by determining the levels of 6-ketoPGF1α and TXB2, respectively [7, 43]. PGA2, PGB2, and PGC2; and PGJ2 and
∆12,14
15-deoxy-
PGJ2 are formed from PGE2 and PGD2, respectively, by non-enzymatic reactions (Fig. 2). Phenotypes of PG synthases have been studied using knockout mice. PGHS-1 and PGHS-2 knockout mice show impaired inflammatory responses. PGHS-1 knockout mice exhibit the reduction of AA-induced ear edema and slightly inhibit macrophage recruitment, whereas
8
ACCEPTED MANUSCRIPT PGHS-2 knockout mice do not show the reduction and suppress acute inflammation. The peritonitis observes only in PGHS-2 knockout mice [44, 45]. Cytosolic PGE synthase (cPGES) knockout mice are perinatal lethal with poor lung development and delayed skin maturation [46, 47]. Membrane-bound PGE synthase-1 (mPGES-1) knockout mice exhibit impaired
T
inflammatory reactions and carcingogenesis suppression [48, 49], whereas mPGES-2 knockout
IP
mice show no specific phenotype [50]. Hematopoietic PGD synthase (H-PGDS) knockout mice
CR
exhibit the suppression of neuroinflammation, demyelination, and carcingogenesis [51-53]; and lipocalin PGD synthase (L-PGDS) knockout mice show impaired sleep regulation, pain sensation,
US
nephropathy, atherosclerosis, and obesity [29, 54-56]. PGFS knockout mice exhibit the
AN
deregulation of adipogenesis and lipogenesis [57]. PGIS knockout mice show high blood
ED
and impaired wound healing [59].
M
pressure and ischemic renal disorders [58]. TXAS knockout mice exhibit mild hemostatic defect
3.1. Prostaglandin G/H synthase
PT
PGHS (EC 1.14.99.1), commonly known as COX, converts AA to to PGH2 via PGG2 (Fig.
CE
3A). PGHS is a bifunctional enzyme with COX and peroxidase (POX) activities, which are responsible for the cyclization of AA and reduction of PGG2, respectively. PGG2 is also reduced
AC
rapidly by other chemical reducing agents because of their unstable nature. PGH2 itself is not physiological nor pharmacological active; instead, it serves as a precursor for other active PGs [3]. PGHS exists as two isoforms, namely PGHS-1 and PGHS-2, also known as COX-1 and COX-2, respectively [60]. Generally, PGHS-1 is expressed constitutively and serves in the regulation of vascular homeostasis and cellular responses to hormonal stimulation, whereas PGHS-2 is expressed
9
ACCEPTED MANUSCRIPT mainly in response to growth factors and inflammatory stimuli [11, 61]. However, PGHS-2 is also expressed in a constitutive manner in a specific tissue such as the kidney, gastrointestinal tract, human fetal brain, thymus, and stomach [62]. PGHS-1 and PGHS-2 are targets for nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit the activity of PGHS-1 and
T
PGHS-2, and thereby the synthesis of PGs, indicating that these lipid mediators are involved in
IP
the occurrence of pain, fever, and inflammation [11, 15]. Aspirin, diclofenac, ibupropen,
CR
indomethacin, meloxivam, and piroxicam are inhibitors for PGHSs [63]. NSAIDs are available for the inhibition of PGHS-1 and PGHS-2, although both enzymes have different selectivity for
US
NSAIDs [64]. PGHS-1 is inhibited by all NSAIDs, whereas PGHS-2 is inhibited by more
AN
specific inhibitors such as DuP697 [65], NS-398 [65], and SC-58125 [66]. PGHS-1 is inhibited by both time-dependent and time-independent inhibition mechanism, depending upon the
M
chemical nature of the inhibitor [67, 68], whereas PGHS-2 is inhibited by a time-dependent
ED
mechanism [69]. The different inhibition is due to the specific residue at position 523, an Ile in PGHS-1 and a Val in PGHS-2 [70, 71]. In addition, PGHS-1 activity is highly specific towards
PT
AA, which has a free carboxyl group, whereas PGHS-2 can efficiently use neutral ester and
CE
amide derivatives of AA as substrates [72].
AC
3.1.1. Enzyme properties
The amino acid sequences of PGHS-1 and PGHS-2 are highly conserved with approximately 90% sequence identity. PGHSs have four domains, including the epidermal growth factor-like (EGF-like), membrane binding, dimerization, and catalytic domains [24, 73]. The signal peptide at the N-terminus and the N-glycosylation sites at Asn68, Asn144, and Asn410 of PGHSs are important contributors to the proper folding of these enzymes [74]. The translation
10
ACCEPTED MANUSCRIPT rate of PGHS-1 is greater than that of PGHS-2 due to a difference in their signal peptides at the N-terminus. The signal peptide of PGHS-1 is in the range of 22 to 24 amino acids, while that of PGHS-2 is always 17 amino acids [11]. PGHS-2 has a instability motif, consisting of 27 amino acids at C-terminal region, which are involved in aspects of protein degradation [75]. The EGF-
T
like domain of PGHSs contains about 50 amino acids with less than 60% sequence identity
IP
between PGHS-1 and PGHS-2. The EGF-like domain also has seven cysteine residues that are
CR
involved in three intramolecular disulfide bonds and four disulfide linkages between the EGFlike and catalytic domains [76]. All PGHSs from mammals include the membrane binding
US
domain as an integral membrane protein, and thus detergent is required for protein solubilization
AN
[77]. The membrane binding domain of PGHSs provides an entrance to the active site [76]. The dimerization domain in PGHSs contributes to dimer assembly via hydrophobic interaction,
M
hydrogen bonding, and salt bridges; dimerization is essential for the catalytic activity of PGHSs
ED
[78]. The catalytic domain is the largest domain among the four domains in PGHSs. This domain contains spatially the distinct COX and POX active sites. The COX active site is located near the
PT
membrane binding domain, whereas the POX active site is located on the surface of the enzyme,
CE
furthest from the membrane binding domain. Arg120, which lies at the edge of the catalytic domain, is linked to the membrane binding domain and regulates access to the active site channel
AC
in PGHSs [76].
The biochemical properties of PGHSs, such as their specific activity, kinetic parameters, optimal temperature and pH, molecular weight, and quaternary structure are summarized in Table 2. PGHSs exist in various mammals including Bos taurus [79], Equus caballus [80], Homo sapiens [60, 81], Mus musculus [82, 83], Neovison vison [84], Oryctolagus cuniculus [85], Ovis aries [86, 87], and Rattus norvegicus [88, 89]. PGHSs also exist in non-mammals including the
11
ACCEPTED MANUSCRIPT aves Gallus gallus [90], the actinopterygii Danio rerio [91], the malacostracas Caprella sp. and Gammarus sp. [92], the corals Gersemia fruticosa [23] and Plexaura homomalla [93], and the florideae Gracilaria vermiculophylla [94]. The activities of PGHSs are generally determined at pH 7.2 or 8.0, and 25 or 37 °C. The kinetic parameters and specific activities of these enzymes
T
have been determined in only four organisms, H. sapiens [60, 81], O. aries [86], M. musculus
IP
[82, 83], and G. vermiculophylla [94]. Note also that the specific activity of O. aries PGHS for
CR
producing PGH2 from the substrate 15-hydroperoxyeicosatetraenic acid (15-HPETE) is measured using only the POX activity. In mammalian PGHSs, the specific activity for producing
US
PGH2 from AA of H. sapiens PGHS-1 is higher than that of M. musculus PGHS-1 or H. sapiens
AN
PGHS-2. However, the specific activity of G. vermiculophylla PGHS-1 was 6.5-fold higher than that of H. sapiens PGHS-1. Recombinant mammalian PGHSs are expressed in insect or yeast
M
host but not in bacterial host because of their lack of a glycosylation system needed for post-
ED
translational modifications of the active enzymes. In contrast, recombinant G. vermiculophylla PGHS-1 can be expressed in Escherichia coli because it does not have glycosylation sites. The
PT
quaternary structures of PGHSs from mammals are dimers, whereas PGHS from the florideae G.
CE
vermiculophylla is a tetramer. Mammalian PGHSs have a conserved binding site for NSAIDs, Arg120, Tyr355, and Ser530. However, the amino acid residues of the binding site of G.
AC
vermiculophylla PGHS-1 for NSAIDs are different with those of mammalian PGHSs, indicating that this enzyme has different inhibitors [94].
3.1.2. Mechanism and active site PGHS is a heme-dependent bifunctional enzyme that catalyzes the cyclization of AA and reduction of PGG2 to PGH2. The proposed reaction mechanism and three-dimensional (3D)
12
ACCEPTED MANUSCRIPT structure (Protein Date Base, PDB No. 1U67) of the active site of PGHS are presented in Fig. 3A. In the first step of PGHS reaction, the pro-S hydrogen abstraction is initiated at C13 of AA by a Tyr385 radical, generating pentadienyl radical between C11 and C15. O2 adds to C11 of the activated AA, resulting in the formation of an endoperoxide between C9 and C11, migration of
T
the carbon radical to C8, and coupling between C8 and C12 to form a cyclopentane ring. In the
IP
next step, the addition of a second O2 to the carbon radical at C15 yields a peroxyl radical, which
CR
formed after hydrogen abstraction by Tyr385 to make PGG2 containing a peroxyl group at C15, which is reduced to PGH2 by the POX activity of PGHS [95]. PGHS-1 from the florideae G.
US
vermiculophylla may have a similar reaction mechanism because the catalytic residue (Tyr385) as
AN
well as residues involved in heme liganding (His207 and His388), hydrogen abstraction (Tyr348 and Gly533), and cyclization (Val349 and Trp387) are absolutely conserved (Table 3). The Arg120
M
residue of mammalian PGHSs is critical for substrate and inhibitor binding as it is involved in
ED
opening the active site; and other residues are involved in substrate binding include Tyr355 and
PT
Ser530.
CE
3.2. Prostaglandin E synthase
PGES (EC 5.3.99.3) converts PGH2 to PGE2 (Fig. 3B) and has been identified only in
AC
mammals, although it can be easily expressed in E. coli. PGESs consist of cPGES, mPGES-1, and mPGES-2 [96]. Both cPGES and mPGES-2 are constitutively expressed. On the other hand, mPGES-1, a key enzyme for the in vivo conversion of PGH2 to PGE2, is involved in various pathophysiological events such as inflammation, fever, pain, female reproduction, tissue repair, and cancer [97], and mPGES-1 is co-regulated with PGHS-2 in A549 cells exposed to interleukin-1β [98]. To catalyze the conversion of AA to PGE2, which requires the sequential
13
ACCEPTED MANUSCRIPT reactions of two enzymes, mPGES-1 preferentially acts in concert with PGHS-2, whereas cPGES and mPGES-2 preferentially acts in concert with PGHS-1 [96]. Human embryonic kidney 293 (HEK293) cells co-expressing mPGES-1 and PGHS-2 produce approximately 2- to 4-fold higher
T
concentration of PGE2 from AA than cells expressing only mPGES-1 [99].
IP
3.2.1. Properties of cPGES
CR
cPGES, a 26 kDa cytosolic protein, has been identified as a heat shock protein 90 (Hsp90)associated protein because the enzyme is regulated by a Hsp (heat shock protein) with a
US
molecular weight (Mw) of 90 kDa. cPGES requires glutathione (GSH) as a cofactor for its
AN
enzymatic activity. cPGES has been found in Bombyx mori [100], D. rerio [101], and H. sapiens [102]. The specific activity and catalytic efficiency (kcat/Km) of H. sapiens cPGES are 0.19 µmol
M
min−1 mg−1 and 0.06 s−1 µM−1, respectively (Table 2). This enzyme is constitutively expressed
PT
3.2.2. Properties of mPGESs
ED
and is not affected by pro-inflammatory stimuli.
CE
mPGESs belong to a superfamily of membrane-associated proteins in eicosanoid and GSH metabolism (MAPEG). These enzymes also require GSH as a cofactor for activity. The MAPEG
AC
superfamily is found in prokaryotes and eukaryotes, however, mPGESs have been discovered only in mammals [103]. mPGES-1s are found in B. taurus [104], D. rerio [101], H. sapiens [97], M. musculus [105], and R. norvegicus [106], Sus scrofa [107]; and mPGES-2s exist in B. taurus [108], H. sapiens [109], Macaca fascicularis [109], and M. musculus [110] (Table 2). The Mws of mPGES-1s range from 15 to 18 kDa, whereas mPGES-2s have more than 30 kDa Mw. The specific activities and kinetic parameters for mPGESs are summarized in Table 2. The kinetic
14
ACCEPTED MANUSCRIPT parameters of mPGES-1s have been measured at pH 8.0 and 24 or 37 °C. The specific activity and catalytic efficiency (kcat/Km) of H. sapiens mPGES-1 [97] are the highest among mPGESs at 51.5 and 5.2-fold higher, respectively, than those of M. fascicularis mPGES-1 [109].
T
3.2.3. Mechanism and active site of mPGES-1
IP
The proposed reaction mechanism is based on the crystal structure of mPGES-1 from H.
CR
sapiens (PDB No. 4AL0) [111] (Fig. 3B). Ser127 of mPGES-1 activates the thiol group of the GSH cofactor, which in turn attacks the endoperoxide oxygen atom at C9 of PGH2, resulting in
US
the cleavage of the O−O bond and the formation of a S−O bond bridging C9 and the thiol group
AN
of GSH. Subsequent proton abstraction at C9 and S−O bond cleavage are mediated by Asp49 with the help of Arg126, resulting in the formation of PGE2 [106]. In the crystal structure, GSH in
M
the active site is coordinated by hydrogen bonds to the side chains of Arg73, Asn74, Glu77, His113,
ED
Tyr117, Arg126, and Ser127 (Fig. 3B). Ser127 of mPGES-1 serves as the catalytic residue; and Asp49
PT
and Arg126 form a salt-bridge and are involved in proton abstraction (Table 3).
CE
3.3. 15-Hydroxyprostaglandin dehydrogenase The conversion of PGE2 to 15-keto-PGE2 is catalyzed by 15-HPGD (EC 1.1.1.141), which
AC
belongs to the short-chain dehydrogenase/reductase (SDR) family (Fig. 3C). Two isoforms, 15HPGD-1 and 15-HPGD-2, have been identified for 15-HPGD. The cofactor of 15-HPGD-1 is NAD+, whereas 15-HPGD-2 uses NADP+ as cofactor. 15-HPGD-1 shows higher specificity toward PG and lipoxin substrates than 15-HPGD-2 [112].
3.3.1. Enzyme properties
15
ACCEPTED MANUSCRIPT 15-HPGDs have only been found in mammals, including B. taurus [113], H. sapiens [113, 114], M. musculus [115], O. cuniculus [116], R. norvegicus [117, 118], and S. scrofa [119]. The biochemical properties of 15-HPGDs are summarized in Table 2. Only 15-HPGD-1 is considered in this review because 15-HPGD-2 does not contribute to the catabolism of PGs [120]. In the
T
comparison of the sequences among the SDR family, 15-HPGD-1 has a well conserved Gly-rich
IP
motif (Gly-X-X-X-Gly-X-Gly) and catalytic triad (Ser-Tyr-Lys). The quaternary structure of 15-
CR
HPGD-1s is a dime with a Mw of 29 kDa. The activities of 15-HPGD-1s have been determined at pH 7.5 or 9.0 and 25 or 37 °C. Bos taurus 15-HPGD-1 has the highest specific activity [113],
M
3.3.2. Mechanism and active site
AN
sapiens 15-HPGD can be well expressed in E. coli.
US
whereas H. sapiens 15-HPGD-1 has the highest turnover number [112]. Notably, recombinant H.
ED
The reaction mechanism of 15-HPGD is presented in Fig. 3C. The catalytic residues Tyr151 and Ser138 are conserved residues in the SDR family (Table 3). Ser138 and Gln148 of 15-HPGD
PT
are involved in the formation of oxygen and hydrogen bonds at the C15 hydroxyl group of
CE
PGE2, respectively [112]. The hydroxyl group of the catalytic Tyr151 assists in the positioning of the C15 hydroxyl group of PGE2 with the help of Lys155. Deprotonation of the C15 hydroxyl
AC
group of PGE2 by Tyr151 and transfer of the hydrogen at C15 to NAD+ yield the product 15keto-PGE2. Based on the 3D structure (PDB No. 2GDZ) of the 15-HPGD active site, Thr11, Ile74, Asn91, Cys182, Val186, and Thr188 interact with the cofactor NAD+ [121].
3.4. Prostaglandin D synthase
16
ACCEPTED MANUSCRIPT PGDS (EC 5.3.99.2) converts PGH2 to PGD2 (Fig. 3D and 3E). PGDSs are classified into two types, H-PGDS and L-PGDS. H-PGDS requires GSH as a cofactor for catalysis because it is associated with the activity of glutathione-S-transferase [122]. Unlike to H-PGDS, L-PGDS does not required GSH as a cofactor; instead, it has an active site with a thiol group from a Cys
IP
T
residue [123].
CR
3.4.1. H-PGDS
H-PGDS is a therapeutic target protein for the design of anti-allergy and anti-inflammation
US
drugs. It is a cytosolic protein and has dimeric structure with a Mw of 23 kDa. H-PGDS binds
AN
not only GSH but also Mg2+ or Ca2+, which can increase the activity of H-PGDS. Binding of Mg2+ ions changes the affinity of H-PGDS for GSH, whereas binding of Ca2+ ions does not
M
change the affinity of H-PGDS [124]. The biochemical properties of H-PGDS are summarized in
ED
Table 2. H-PGDSs from H. sapiens, M. musculus, and R. norvegicus [125], and Schistosoma mansoni [22] have been reported, and their activities have been determined at pH 8.0 and 25 °C.
PT
Among the reported H-PGDSs, the specific activity of H-PGDS from R. norvegicus is the
CE
highest at 1.1-fold higher than that of H. sapiens. The reaction of H-PGDS is initiated by the binding of the thiolate anion of GSH to H-PGDS
AC
via the catalytic Tyr8 residue. The activated thiolate anion attacks the endoperoxide oxygen atom at C11 of PGH2 and forms a S−O bond. PGH2 is stabilized by a hydrogen bonding interaction between the amide nitrogen of glycine in GSH and the endoperoxide oxygen atom at C9 of PGH2. The labile S−O bond breaks to form a carbonyl group at C11 and to release the product PGD2 [124, 126] (Fig. 3D). The crystal structure of H-PGDS has been determined for the enzyme from H. sapiens (PDB No. 1IYH). In the active site, Tyr8, Arg14, and Trp104 are essential residues for
17
ACCEPTED MANUSCRIPT the activation, stabilization, and transfer of the thiol group in GSH, respectively, and other important residues include Asp93, Asp96, and Asp97, which are involved in metal coordination (Table 3).
T
3.4.2. L-PGDS
IP
L-PGDS was isolated from the rat brain [127]. It has a monomeric structure with a Mw of
CR
about 26 kDa. L-PGDS is identical to a beta-trace protein, and it is the first member of the lipocalin family and a major protein in human cerebrospinal fluid [128, 129]. L-PGDSs have
US
been reported in mammals, including B. taurus [130], H. sapiens [131], and M. musculus [132],
AN
and non-mammals, including D. rerio [101] and G. gallus [132], and their activities have been determined at pH 8.0 and 25 °C (Table 2). Among L-PGDSs, the specific activity of M. musculus
M
L-PGDS is the highest at 13.4-fold higher than that of R. norvegicus H-PGDS.
ED
The reaction mechanism of L-PGDS is similar to that of H-PGDS (Fig. 3E). The binding of PGH2 to the active site pocket of L-PGDS positions the endoperoxide oxygen at C-11 of PGH2 in
PT
close proximity to the thiol group of Cys65. The role of the Cys residue is the same as that of
CE
GSH in the reaction of H-PGDS. A S−O bond is formed at C11 of PGH2 by nucleophilic attack of thiolate anion of the catalytic Cys65 residue. The Ser45, Thr67, and Ser81 residues form a
AC
hydrogen bonding network that is involved in activating the thiol group of Cys65. The labile S−O bond is autonomously broken with proton rearrangement occurring at the hydroxyl group of Ser45, releasing the product PGD2. The Cys89 and Cys186 residues of L-PGDS form disulfide bridges, which plays an important role for the stabilization of the structure of L-PGDS [133]. Cys89 and Cys186 are conserved among many but not all lipocalin enzymes, whereas Cys65 is conserved in all lipocalin enzymes. Trp54 and His111 are involved in the release of PGD2.
18
ACCEPTED MANUSCRIPT
3.5. Prostaglandin F synthase PGFS (EC 1.1.1.188) is an enzyme that catalyzes the formation of PGF2α. PGFSs exist as three isoforms: PGFS-1, PGFS-2, and PGFS-3. PGFSs are classified based on their substrate. PGFS-1
T
and PGFS-3 convert PGH2 and PGE2 to PGF2α, respectively, while PGFS-2 converts PGD2 to
IP
9α,11β-PGF2α, which is a PGF2α stereoisomer. Most of these enzymes belong to the aldo-keto
CR
reductase (AKR) family, which requires NADPH as a cofactor. PGFS-1s from B. taurus [134], H. sapiens [135], Leishmania major [136], M. musculus [135, 137], S. scrofa [107, 137],
US
Trypanosoma brucei [138], and Trypanosoma cruzi [139]; PGFS-2s from B. taurus [140], and H.
AN
sapiens [141]; and PGFS-3 from S. scrofa [142] have been reported (Table 2). In this review, only PGFS-1 and PGFS-2 are introduced because the activity of PGFS-3 is similar to that of 15-
ED
M
HPGD.
3.5.1. PGFS-1
PT
PGFS-1 catalyzes the conversion of PGH2 to PGF2α, which requires NADPH or NADH as
CE
cofactor. PGFS-1s from various mammals and non-mammals have been identified (Table 2). PGFS-1 can be well expressed in E. coli. The specific activities and kinetic parameters of PGFS-
AC
1s have been determined at pH 7.0 or 7.5 and at 24, 25, or 27 °C. The specific activity and catalytic efficiency (kcat/Km) of PGFS-1 from T. brucei are 2 µmol min−1 mg−1 and 0.79 s−1 µM−1, respectively, which correspondingly represent the highest values for the conversion of PGH2 to PGF2α among the reported PGFS-1s [138]. The reaction mechanism and crystal structure of T. brucei PGFS-1 (PDB No. 1VBJ) are represented in Fig. 3F. The His110 residue of PGFS-1 and the cofactor NADPH are essential for
19
ACCEPTED MANUSCRIPT PGH2 reduction. Lys77 and Asp47 are involved in the protonation of His110, which is in turn positioned to allow a hydrogen bonding interactions to C9 or C11 endoperoxide oxygen of PGH2 (Table 2). As a result, PGH2 is protonated and reduced to PGF2α [74]. Among AKR family members, T. brucei PGFS-1 has a highly conserved catalytic tetrad that consists of the Asp47,
IP
T
Lys77, Try79, and His110 residues.
CR
3.5.2. PGFS-2
PGDS-2 catalyzes the conversion of PGH2 to 9α,11β-PGF2α that requires NADPH as a
US
cofactor. PGFS-2s have been identified in B. taurus [140] and H. sapiens [141]. However, the
AN
specific activity and kinetic parameters of PGFS-2 have only been determined in the enzyme from H. sapiens. The Mw of PGFS-2 from H. sapiens is 37 kDa. PGFS-2 catalyzes a reversible
M
reaction depending on the pH [143]. PGFS-2 catalyzes the reduction of PGD2 to PGF2 at low pH
ED
and the oxidation of PGF2 to PGD2 at high pH [144], and both reactions are affected by the presence of acidic or basic residues in the active site [141, 143, 145].
PT
The reaction of PGFS-2 is involved in a hydride transfer in PGFS-2 from NADPH to the
CE
carbonyl oxygen at C11 of PGD2. Tyr55 and His117 form hydrogen bonds to the C11 oxygen of cyclopentane of PGD2 (Table 3), which is protonated and reduced to 9α,11β-PGF2α [143] (Fig.
AC
3G). A catalytic tetrad consisting of Tyr55 and His117 in hydrogen bond networks to Asp50 and Lys84 provides an environment conducive for hydride transfer from the nicotinamide ring of NADPH [144].
3.6. Prostaglandin I synthase 3.6.1. Enzyme properties
20
ACCEPTED MANUSCRIPT PGIS (EC 5.3.99.4), also called as prostacyclin synthase or cytochrome P450 (CYP) 8A1, is a member of the CYP enzymes, which requires a heme group for catalysis. PGIS catalyzes the conversion of PGH2 to PGI2, which is non-enzymatically hydrated to yield 6-keto-PGF1α. PGISs have been identified in B. taurus [146], D. rerio [101], H. sapiens [147], M. musculus [148], and
T
R. norvegicus [149]. PGIS enzymes exist as a monomer with a Mw of 56 kDa (Table 2). The
IP
kinetic parameters and specific activities of these enzymes have been determined in B. taurus
CR
and H. sapiens at pH 7.5 and 23 °C. The specific activity of H. sapiens PGIS is 267-fold higher than that of B. taurus PGIS (Table 2). Notably, the specific activity of B. taurus PGIS was
US
determined using PGH2 as substrate, whereas the specific activity of H. sapiens PGIS was
AN
determined using U46619 as a substrate, which is a stable synthetic analog of PGH2.
ED
3.6.2. Mechanism and active site
M
Additionally, recombinant H. sapiens PGIS can be well expressed in E. coli [147].
In the reaction of PGIS, heme-iron (FeIII), which is coordinated by the thiolate anion of Cys441,
PT
transfers an electron to the endoperoxide oxygen atom at C11 of PGH2 to induce the cleavage of
CE
the O−O bond, resulting in the formation of a FeIV-porphyrin to oxygen bond at C11 and an alkoxy radical at C9 [150] (Fig. 3H). The alkoxy radical attacks the π-bond at the C6 and C9 to
AC
produce a five-member ring and a carbon radical at C5. The carbon radical at C5 then donates an electron to FeIV-porphyrin to form a C5 carbocation. Subsequent loss of the proton at C6 and formation of a double bond between C5 and C6 yield PGI2 [151]. Based on the crystal structure of H. sapiens PGIS (PDB No. 2IAG), Cys441 in the active site is involved in heme binding, and Ala447, which is located very close to Cys441, stabilizes the conformation of PGIS [147] (Table 3).
21
ACCEPTED MANUSCRIPT 3.7. Thromboxane A synthase 3.7.1 Enzyme properties TXAS (EC 5.3.99.5) catalyzes not only the conversion of PGH2 to TXA2 but also the cleavage of PGH2 to 12-hydroxy-heptadecatrienoic acid (12-HHT) and malondialdehyde, which are
T
formed stoichiometrically in the same amounts as TXA2 [152]. 12-HHT, an important lipid
IP
mediator of platelet plug formation, is formed by physiologically stimulated human platelets
CR
[153]. TXAS is a ferrihemoprotein and a member of CYP enzymes. TXASs have been identified in Danio rerio [101], H. sapiens [154], M. musculus [155, 156], R. norvegicus [157], and S.
US
scrofa [158]. H. sapiens TXAS can be well expressed in E. coli with the help of bacterial
AN
chaperones [159]. The Mw of TXAS is about 60 kDa. The kinetic parameters of TXASs have been determined at pH 7.5 and 23 or 30 °C (Table 2). The specific activity and Km value of H.
ED
M
sapiens TXAS were 52-and 1.7-fold higher, respectively, than those of S. scrofa TXAS.
3.7.2 Mechanism and active site
PT
The reaction mechanism of TXAS has been proposed based on the homology model of TXAS
CE
using Build Homology Models module in the MODELER application of Discovery Studio 4.0 (Accerlys, San Diego, CA, USA) constructed from the crystal structure of CYP from Bacillus
AC
megaterium as a template (PDB No. 1BU7) (Fig. 3I) [159]. The heme-iron (FeIII-porphyrin) in TXAS is coordinated to the thiolate anion of Cys480. The heme-iron reacts with the endoperoxide oxygen at C9 of PGH2 to induce cleavage of the O−O bond, resulting in the formation of a FeIVporphyrin and alkoxy radical at C11. The radical at C11 then donates an electron to FeIVporphyrin, resulting in the cleavage of C11 and C12 of the five-carbon ring and formation of an allylic radical, followed by ionic rearrangement to finally yield TXA2. The active site of TXAS
22
ACCEPTED MANUSCRIPT include Asn110, Arg413, and Arg478, which interact with the A- or D-ring of the heme, and Trp133 and Arg137 [160]. Additionally, Arg86, Phe127, Met237, and Leu521 of TXAS are involved in the stabilization of binding pocket [159] (Table 3)
T
4. Synthesis of prostaglandins
IP
4.1 Chemical synthesis
CR
Synthesis of PGs have been carried out via modified and improved chemical reactions based
US
on the use of Corey’s lactone as a synthetic intermediate. PGF2α is chemically synthesized through 20-step reactions which include Diels-Alder reaction, Baeyer-Villiger oxidation, Collins
AN
oxidation, Horner-Wadsworth-Emmons reaction, and Wittig reaction [8, 161]. In 2012, chemical
M
synthesis of PGF2α using 7-step reactions was developed [9]. Various types of PG analogues, including PGH2, PGE1, PGE2, PGF2α, and PGI2 analogues, have also been synthesized
ED
chemically [14]. PG analogues are designed to prostaglandin receptors, and have been used in
AC
4.2.1 Mammals
CE
4.2 Biosynthesis
PT
the treatment of open angle glaucoma, among other applications.
Mammalian PGs are the most widely studied and well characterized among PGs. The mammalian biosynthetic pathway from phospholipid to PGE2 is presented in Fig. 4. The starting material for synthesis of PGs, AA, is released from phospholipids of the endoplasmic reticulum (ER) and nuclear membrane by cytosolic phospholipase A2 (cPLA2), a key enzyme in eicosanoids production [162]. The released AA is metabolized to PGH2 via PGG2 by PGHS in the COX pathway. Various PGs in mammals are derived from PGH2 by PG synthases, including
23
ACCEPTED MANUSCRIPT PGHS, PGES, PGDS, PGFS, PGIS, and TXAS. PGE2 is synthesized from PGH2 by PGES in cells or by non-enzymatic reactions [163]. PGHS resides in the ER and nuclear membrane, and PGH2 is isomerized to various PGs by specific PG synthases in tissues. PGDS is found in brain and mast cells; PGFS is found in the uterus; PGIS is found in endothelium cells; and TXAS is
T
mainly found in platelets and macrophages [3]. PGs are released from cells by a PG transporter
IP
(PGT), and the released PGs then interact with the specific PG-receptors on cell surfaces. PGT is
CR
a lactate/PG anion exchanger [164], which mediates the energetically active uptake into the cell of PGE2, PGF2α, PGD2, and PGI2, but TXA2 [165]. PGT, a solute carrier organic anion
US
transporter family encoded by the SLCO2A1, is a member of the 12-membrane-spanning organic
AN
anion-transporting polypeptide superfamily of transporters. PGT has been discovered in R. norvegicus [166], M. musculus [167], and H. sapiens [168, 169]. PGT belongs to the organic
M
anion transporter family that has multi-specific system in substrate recognition due to its
PT
phosphorylation site [170].
ED
structure features such as 12-transmembrane domains and multiple glycosylation or
CE
4.2.2 Corals
In corals, biosynthesis of PGs from AA occurs by a different pathway than those of mammals
AC
and florideae [171, 172]. In Plexaura homomalla, AA is converted by 8-LOX to 8-HPETE, which is in turn transformed to clavulone I, a PG analogue, by the reactions of a fusion protein of 8-LOX and allene oxide synthase (AOS); and a putative cyclase (Fig. 4). Other major PGs that are found in P. homomalla include 15R-PGA2, 15R-PGA2-methyl ester (Me), 15R-acetate-PGA2Me, PGA2-Me, 15R-PGE2-Me and PGE2-Me [173-175]. The arctic coral Gersemia fruticosa, which has PGHS and 8-LOX-AOS enzymes, produces PGD2, PGE2, PGF2α, and 15-keto-PGF2α
24
ACCEPTED MANUSCRIPT from AA [176, 177]. P. homomalla 15R-PGHS and G. fruticosa PGHS have been cloned into Sf9 insect cells and characterized [23]. P. homomalla 15R-PGHS converts AA to 15R-PGE2, 15R-PGD2, and 15R-PGF2α via the intermediates 15R-PGG2 and 15R-PGH2, with 11R-HETE, 15R-HETE, and 12R-HHT as by-products [93]. The resulting 15R-PGE2 is converted to 15R-
T
acetate-PGA2-Me through the methylation and acetylation reactions by the commercial lipases
IP
from Candida antarctica and Humicola lanuginosa [178]. PGHS from G. fruticosa converts AA
CR
to PGE2, PGD2, and PGF2α with 11R-HETE, 15S-HETE, and HHT as by-products. This enzyme also catalyzes the production of several other PGs via the intermediates PGG2 and PGH2 from
US
AA, and the pathway for the biosynthesis of these other PGs is similar to that of 15R-PGHS from
AN
P. homomalla.
M
4.2.3 Florideae
ED
PGs have been discovered in various species of Gracilaria, which are a class of red algae. PGA2, PGE2, and 15-keto-PGE2 are found in G. asiatica, also known as G. verrucosa [179-181],
PT
and PGE2 and PGF2α are found in G. lichenoids [182]. Raw seaweed of G. gigas (10 g, w/w) is
CE
converts 2 mg AA to 4.9 µg PGE2 at 37 °C for 1 h, indicating that it has the enzymes to produce PGs [183]. PGA2, 8-iso-PGA2, PGE2, and 15-keto-PGE2 have all been identified by metabolic
AC
profiling of G. vermiculophylla [184, 185]. PGHS from G. vermiculophylla is the first nonmammalian PGHS to exhibit different enzyme properties compared to mammalian PGHSs. This enzyme can be expressed in E. coli without eukaryotic modifications [94, 186]. Recombinant E. coli expressing G. vermiculophylla PGHS can produce up to 2.7 mg/L PGF2α from exogenous AA without by-products like 11-hydroxyeicosatetraenoic acid (HETE) and 15-HETE [186]. PGF2α is also obtained from the reduction of PGH2 by SnCl2. The recombinant E. coli can
25
ACCEPTED MANUSCRIPT produce up to 130 mg/L of total PGs, which is the highest PGs production among cells [187]. Additionally, G. vermiculophylla PGHS also converts AA to PGE2, PGF2α, and PGD2 [94]. Levels of PG production by this algal enzyme is in the mg/L range, whereas mammalian PGHSs typically yield PGs in the ng/L range. This concentration difference may be due to the different
T
expression levels of algal and mammal PGHSs in E. coli, although the biosynthesis pathway of
CR
IP
PGs in florideae is similar to that of mammals.
4.2.4 Yeast and Fungi
US
The formation of PGs has been identified in pathogenic yeast and fungi. Pathogenic yeast,
AN
including the Saccharomycetes class, Candida albicans and Candida parapsilosis, and the Tremellomycetes class Cryptococcus neoformans, have the potential to influence immune
M
responses because they can produce immunomodulatory PGs from AA [188, 189]. C. albicans
ED
SC5314 produces 1 ng/L PGE2 from AA. Fatty acid desaturase homolog (Ole2) and multicopper oxidase homolog (Fet3) may be involved in the biosynthesis pathway of PGE2 in C. albicans
PT
because PGE2 production in ole2 or fet3-deficient strains is reduced to approximately 30% [190].
CE
However, Ole2 is not involved in the biosynthesis PGs in C. parapsilosis because PGE2 production in ole2-deficient mutant remains at similar level to that of the wild-type cells [189]. C.
AC
neoformans produces approximately 0.12 µg/L PGs including the PGE1−3 series and PGF2α [188]. The production of PGE2 and PGF2α by C. neoformans is inhibited by polyphenolic molecules such as caffeic acid, resveratrol, and nordihydroguaiaretic acid. These molecules have also been used as inhibitors of mammalian PG synthases. However, C. neoformans lacks PG synthases, although it does have a laccase. Laccase catalyzes the conversion of PGE2 from PGG2, however, is not involved in the conversion of AA to PGH2. Interestingly, loss of PG production is
26
ACCEPTED MANUSCRIPT observed in a laccase encoding gene (lac1)-deficient strain of C. neoformans [191], suggesting that the biosynthesis pathway of PGs in C. neoformans is different from those of mammals, corals, and florideae. Pathogenic fungi, including the Zygomycetes class Absidia corymbifera, the
T
Sordariomycetes class Fusarium dimerum and Sporothrix schenckii, the Eurotiomycetes class
IP
Aspergillus fumigatus, Blastomyces dermatitidis, Epidermophyton floccosum, Histoplasma
CR
capsulatum, Microsporum canis, Penicillium citrinum, Penicillium notatum, Penicillium piscarium, and the Mucoromycotina class Rhizopus pusillus produce 0.26−3.3 µg/L of PGE2,
US
PGF2α, and PGD2 when supplied with 302 mg/L AA [25]. However, the exact biosynthesis
AN
pathways of PGs in these fungi have yet to be characterized.
M
5. Future perspectives
ED
PGs have been manufactured by chemical synthesis. Several chemical methods have been developed to achieve for PGs synthesis. However, chemical methods are required at least 7-step
PT
reactions. In contrast, PGs can also be synthesized by biotechnological methods using PG
CE
synthases with 2- or 3-step reactions and recombinant cells expressing 2 or 3 PG synthases. However, the biotechnological methods for PGs synthesis are still in the early stage.
AC
Biotechnological methods have some advantages such as environmentally friendly, easy purification, stereospecific conversion, mild reaction conditions, and possible of large scale production with a high yield. Thus, in the future, PGs may be industrially produced using biotechnological methods. In this section, PGs synthesis using microbial expression systems are summarized. Moreover, metabolically engineered cells are suggested for PGs biosynthesis using microbial systems.
27
ACCEPTED MANUSCRIPT
5.1 Microbial expression systems for prostaglandin synthesis Generally, mammalian enzymes need post-translational modifications for activity and stability. Among PG synthases, PGHS requires N-glycosylation for full functional activity and therefore
T
cannot be expressed in E. coli, whereas PGES, 15-HPGD, PGDS, PGFS, PGIS, and TXAS can
IP
be heterologously expressed in E. coli. HEK293 and Chinese hamster ovary (CHO) cells, which
CR
are derived from mammals, have been used in the expression systems of PGHS. These hosts have some advantages, such as secretion of membrane enzymes and identical post-translational
US
modification for mammalian enzymes. However, they have also some disadvantages, such as
AN
expensive media, low enzyme expression levels, and difficulty in scale-up production. On the other hand, microbial expression systems, such as E. coli, Bacillus subtilis, Pichia pastoris,
M
Saccharomyces cerevisiae, and Aspergillus nidulans hosts, have been used extensively for the
ED
production of a diverse range of metabolites in industry applications because they have many advantages such as low cost, simple gene manipulation, easy and rapid expression, rapid growth,
PT
inexpensive medium, and simple culture conditions [192].
CE
PGHS-2 can be expressed at a high level in P. pastoris [193-195]. The co-expression of PGconverting enzyme with PGHS exhibits higher activity than the expression of PG-converting
AC
enzyme alone [99, 196]. The expression level of PGES in E. coli host is significantly increased by modifying the usage frequency of certain codons [197]. Coupled expression of PGHS with other PG-converting enzymes from M. musculus in S. cerevisiae has been used successfully to produce 6-keto-PGF1α, TXB2, and PGF2α from AA [198]. Recently, the expression of PGHS from G. vermiculophylla in E. coli has yielded the highest levels of PGs among PGHSs reported to date [187]. These results suggest that various PGs can be efficiently synthesized using coupled
28
ACCEPTED MANUSCRIPT expression system of G. vermiculophylla PGHS with other PG-converting enzymes. Therefore, non-mammalian sources of PG synthases and microbial expression systems may be the key to high-level production of PGs from AA.
T
5.2 Metabolic engineering for prostaglandin synthesis
IP
Although the conversion of DGLA, AA, and EPA to PGs by PG synthases has been
CR
demonstrated to be feasible, there are, however, limitations for the biosynthesis of PGs owing to the high costs of these substrates. Thus, allowing the synthesis of PGs to use inexpensive glucose
US
or glycerol through metabolic engineering is highly desirable from an economic standpoint. The
AN
enzymes related to the pathways for the conversion of acetyl-CoA to unsaturated fatty acids include acetyl-CoA carboxylase, fatty acid synthases, elongases, and desaturases [199] (Fig. 5).
M
Genes encoding these enzymes have been introduced into S. cerevisiae [200], Mortierella alpina
ED
[201-203], and Yarrowia lipolytica [204], and these cells are capable of producing unsaturated fatty acids, such as DGLA, AA, and EPA, from glucose or glycerol. Metabolically engineered M.
PT
alpina produces 4.9 and 2.9 g/L AA from glycerol and glucose, respectively [202, 203]. Because
CE
PG synthases convert unsaturated fatty acids such as DGLA, AA, and EPA to PGs, metabolically engineered cells expressing unsaturated fatty acid-producing enzymes together with PG
AC
synthases may be used for the inexpensive biosynthesis of PGs from glucose or glycerol.
6. Conclusion PGs are the important lipid mediators and are biosynthesized by PG synthases, including PGHS, PGES, 15-HPGD, PGDS, PGFS, PGIS, and TXAS. This review summarizes the biochemical properties, reaction mechanisms, and active site details of these PG synthases as
29
ACCEPTED MANUSCRIPT well as the biosynthesis of PGs in mammals, corals, florideae, and fungi. Although most PG synthases have been reported in mammals, similar enzymes can be found in yeast and fungi, as various PGs have been found in these organisms. PGHS from florideae has been expressed in E. coli, and this enzyme exhibits the highest activity among the reported PGHSs, indicating that the
T
non-mammalian enzyme sources and microbial expression systems may be the key to high-level
IP
production of PGs. Metabolically engineered microbial cells expressing unsaturated fatty acid-
CR
producing enzymes together with PG synthases may be used for the inexpensive biosynthesis of
US
PGs from glucose or glycerol.
AN
Acknowledgments
M
This study was funded by the Mid-Career Researcher Program, through the National Research
ED
Foundation grant funded by the Ministry of Science, ICT and Future Planning, Republic of
AC
CE
PT
Korea (No. 2016R1A2B3006881).
30
ACCEPTED MANUSCRIPT References [1] Leonard AE, Pereira SL, Sprecher H, Huang YS. Elongation of long-chain fatty acids. Prog Lipid Res 2004;43:36-54. [2] Horn T, Adel S, Schumann R, Sur S, Kakularam KR, Polamarasetty A, Redanna P, Kuhn H,
T
Heydeck D. Evolutionary aspects of lipoxygenases and genetic diversity of human leukotriene
IP
signaling. Prog Lipid Res 2015;57:13-39.
CR
[3] Funk CD. Prostaglandins and leukotrienes: advances in eicosanoid biology. Science
US
2001;294:1871-5.
[4] Buczynski MW, Dumlao DS, Dennis EA. Thematic Review Series: Proteomics. An integrated
AN
omics analysis of eicosanoid biology. J Lipid Res 2009;50:1015-38. [5] Von Euler US. To the knowledge of the pharmacological effects of native secretions and
M
extracts of male accessory glands. Naunyn Schmiedeberg's Arch Pharmacol 1934;175:78-84.
ED
[6] Bergstrom S, Sjovall J. The isolation of prostaglandin. Acta Chem Scand 1957;11:1086-1086.
PT
[7] Collins PW, Djuric SW. Synthesis of therapeutically useful prostaglandin and prostacyclin analogs. Chem Rev 1993;93:1533-1564.
CE
[8] Corey EJ, Weinshenker NM, Schaaf TK, Huber W. Stereo-controlled synthesis of prostaglandins F2α and E2 (dl). J Am Chem Soc 1969;91:5675-7.
AC
[9] Coulthard G, Erb W, Aggarwal VK. Stereocontrolled organocatalytic synthesis of prostaglandin PGF2α in seven steps. Nature 2012;489:278-81. [10] Harizi H, Corcuff JB, Gualde N. Arachidonic-acid-derived eicosanoids: roles in biology and immunopathology. Trends Mol Med 2008;14:461-9. [11] Simmons DL, Botting RM, Hla T. Cyclooxygenase isozymes: the biology of prostaglandin synthesis and inhibition. Pharmacol Rev 2004;56:387-437.
31
ACCEPTED MANUSCRIPT [12] Onguru O, Casey MB, Kajita S, Nakamura N, Lloyd RV. Cyclooxygenase-2 and thromboxane synthase in non-endocrine and endocrine tumors: a review. Endocr Pathol 2005;16:253-77. [13] Park JY, Pillinger MH, Abramson SB. Prostaglandin E2 synthesis and secretion: the role of
T
PGE2 synthases. Clin Immunol 2006;119:229-40.
CR
pulmonary arterial hypertension. Respir Med 2010;104:9-21.
IP
[14] Mubarak KK. A review of prostaglandin analogs in the management of patients with
[15] Ricciotti E, FitzGerald GA. Prostaglandins and inflammation. Arterioscler Thromb Vasc
US
Biol 2011;31:986-1000.
AN
[16] Hirata T, Narumiya S. Prostanoid receptors. Chem Rev 2011;111:6209-30. [17] Jiang J, Dingledine R. Prostaglandin receptor EP2 in the crosshairs of anti-inflammation,
M
anti-cancer, and neuroprotection. Trends Pharmacol Sci 2013;34:413-23.
ED
[18] Alhouayek M, Muccioli GG. COX-2-derived endocannabinoid metabolites as novel inflammatory mediators. Trends Pharmacol Sci 2014;35:284-92.
PT
[19] Cha YI, Solnica-Krezel L, DuBois RN. Fishing for prostanoids: deciphering the
CE
developmental functions of cyclooxygenase-derived prostaglandins. Dev Biol 2006;289:263-72. [20] Rowley AF, Vogan CL, Taylor GW, Clare AS. Prostaglandins in non-insectan invertebrates:
AC
recent insights and unsolved problems. J Exp Biol 2005;208:3-14. [21] Maizels RM, Yazdanbakhsh M. Immune regulation by helminth parasites: cellular and molecular mechanisms. Nat Rev Immunol 2003;3:733-44. [22] Herve M, Angeli V, Pinzar E, Wintjens R, Faveeuw C, Narumiya S, Capron A, Urade Y, Capron M, Riveau G, Trottein F. Pivotal roles of the parasite PGD2 synthase and of the host D prostanoid receptor 1 in schistosome immune evasion. Eur J Immunol 2003;33:2764-72.
32
ACCEPTED MANUSCRIPT [23] Koljak R, Jarving I, Kurg R, Boeglin WE, Varvas K, Valmsen K, Ustav M, Brash AR, Samel N. The basis of prostaglandin synthesis in coral: molecular cloning and expression of a cyclooxygenase from the Arctic soft coral Gersemia fruticosa. J Biol Chem 2001;276:7033-40. [24] Gupta K, Selinsky BS. Bacterial and algal orthologs of prostaglandin H(2)synthase: novel
T
insights into the evolution of an integral membrane protein. Biochim Biophys Acta
IP
2015;1848:83-94.
CR
[25] Noverr MC, Toews GB, Huffnagle GB. Production of prostaglandins and leukotrienes by pathogenic fungi. Infect Immun 2002;70:400-2.
US
[26] Trzaskowski B, Latek D, Yuan S, Ghoshdastider U, Debinski A, Filipek S. Action of
AN
molecular switches in GPCRs-theoretical and experimental studies. Curr Med Chem 2012;19:1090-109.
M
[27] Gilman AG. G proteins: transducers of receptor-generated signals. Annu Rev Biochem
ED
1987;56:615-49.
[28] Narumiya S, FitzGerald GA. Genetic and pharmacological analysis of prostanoid receptor
PT
function. J Clin Invest 2001;108:25-30.
CE
[29] Eguchi N, Minami T, Shirafuji N, Kanaoka Y, Tanaka T, Nagata A, Yoshida N, Urade Y, Ito S, Hayaishi O. Lack of tactile pain (allodynia) in lipocalin-type prostaglandin D synthase-
AC
deficient mice. Proc Natl Acad Sci U S A 1999;96:726-30. [30] Lewis RA, Soter NA, Diamond PT, Austen KF, Oates JA, Roberts LJ, 2nd. Prostaglandin D2 generation after activation of rat and human mast cells with anti-IgE. J Immunol 1982;129:162731. [31] Matsuoka T, Hirata M, Tanaka H, Takahashi Y, Murata T, Kabashima K, Sugimoto Y, Kobayashi T, Ushikubi F, Aze Y, Eguchi N, Urade Y, Yoshida N, Kimura K, Mizoguchi A, Honda
33
ACCEPTED MANUSCRIPT Y, Nagai H, Narumiya S. Prostaglandin D2 as a mediator of allergic asthma. Science 2000;287:2013-7. [32] Sugimoto Y, Yamasaki A, Segi E, Tsuboi K, Aze Y, Nishimura T, Oida H, Yoshida N, Tanaka T, Katsuyama M, Hasumoto K, Murata T, Hirata M, Ushikubi F, Negishi M, Ichikawa A,
T
Narumiya S. Failure of parturition in mice lacking the prostaglandin F receptor. Science
IP
1997;277:681-3.
CR
[33] Saito O, Guan Y, Qi Z, Davis LS, Komhoff M, Sugimoto Y, Narumiya S, Breyer RM, Breyer MD. Expression of the prostaglandin F receptor (FP) gene along the mouse genitourinary
US
tract. Am J Physiol Renal Physiol 2003;284:F1164-70.
AN
[34] Noda M, Kariura Y, Pannasch U, Nishikawa K, Wang L, Seike T, Ifuku M, Kosai Y, Wang B, Nolte C. Neuroprotective role of bradykinin because of the attenuation of pro-inflammatory
M
cytokine release from activated microglia. J Neurochem 2007;101:397-410.
ED
[35] Kawabe J, Ushikubi F, Hasebe N. Prostacyclin in vascular diseases. - Recent insights and future perspectives. Circ J 2010;74:836-43.
CE
Fed Proc 1987;46:133-8.
PT
[36] Ogletree ML. Overview of physiological and pathophysiological effects of thromboxane A2.
[37] Hirata M, Hayashi Y, Ushikubi F, Yokota Y, Kageyama R, Nakanishi S, Narumiya S.
20.
AC
Cloning and expression of cDNA for a human thromboxane A2 receptor. Nature 1991;349:617-
[38] Jones DA, Fitzpatrick FA. Thromboxane A2 synthase. Modification during "suicide" inactivation. J Biol Chem 1991;266:23510-4. [39] Feletou M, Vanhoutte PM, Verbeuren TJ. The thromboxane/endoperoxide receptor (TP): the common villain. J Cardiovasc Pharmacol 2010;55:317-32.
34
ACCEPTED MANUSCRIPT [40] Harmon GS, Lam MT, Glass CK. PPARs and lipid ligands in inflammation and metabolism. Chem Rev 2011;111:6321-40. [41] Lu D, Han C, Wu T. 15-hydroxyprostaglandin dehydrogenase-derived 15-ketoprostaglandin E2 inhibits cholangiocarcinoma cell growth through interaction with PPARγ,
T
SMAD2/3, and TAP63 proteins. J Biol Chem 2013;288:19484-502.
IP
[42] Lu D, Han C, Wu T. 15-PGDH inhibits hepatocellular carcinoma growth through 15-keto-
CR
PGE2/PPARγ-mediated activation of p21WAF1/Cip1. Oncogene 2014;33:1101-12.
pathways. New Compr Biochem 2002;36:341-371.
US
[43] Smith WL, Murphy RC. The eicosanoids: cyclooxygenase, lipoxygenase, and epoxygenase
AN
[44] Morham SG, Langenbach R, Loftin CD, Tiano HF, Vouloumanos N, Jennette JC, Mahler JF, Kluckman KD, Ledford A, Lee CA, Smithies O. Prostaglandin synthase 2 gene disruption causes
M
severe renal pathology in the mouse. Cell 1995;83:473-82.
ED
[45] Langenbach R, Loftin C, Lee C, Tiano H. Cyclooxygenase knockout mice: models for elucidating isoform-specific functions. Biochem Pharmacol 1999;58:1237-46.
PT
[46] Grad I, McKee TA, Ludwig SM, Hoyle GW, Ruiz P, Wurst W, Floss T, Miller CA, 3rd,
2006;26:8976-83.
CE
Picard D. The Hsp90 cochaperone p23 is essential for perinatal survival. Mol Cell Biol
AC
[47] Nakatani Y, Hokonohara Y, Kakuta S, Sudo K, Iwakura Y, Kudo I. Knockout mice lacking cPGES/p23, a constitutively expressed PGE2 synthetic enzyme, are peri-natally lethal. Biochem Biophys Res Commun 2007;362:387-92. [48] Trebino CE, Stock JL, Gibbons CP, Naiman BM, Wachtmann TS, Umland JP, Pandher K, Lapointe JM, Saha S, Roach ML, Carter D, Thomas NA, Durtschi BA, McNeish JD, Hambor JE, Jakobsson PJ, Carty TJ, Perez JR, Audoly LP. Impaired inflammatory and pain responses in mice
35
ACCEPTED MANUSCRIPT lacking an inducible prostaglandin E synthase. Proc Natl Acad Sci U S A 2003;100:9044-9. [49] Sasaki Y, Kamei D, Ishikawa Y, Ishii T, Uematsu S, Akira S, Murakami M, Hara S. Microsomal prostaglandin E synthase-1 is involved in multiple steps of colon carcinogenesis. Oncogene 2012;31:2943-52.
T
[50] Jania LA, Chandrasekharan S, Backlund MG, Foley NA, Snouwaert J, Wang IM, Clark P,
IP
Audoly LP, Koller BH. Microsomal prostaglandin E synthase-2 is not essential for in vivo
CR
prostaglandin E2 biosynthesis. Prostaglandins Other Lipid Mediat 2009;88:73-81. [51] Rajakariar R, Hilliard M, Lawrence T, Trivedi S, Colville-Nash P, Bellingan G, Fitzgerald
US
D, Yaqoob MM, Gilroy DW. Hematopoietic prostaglandin D2 synthase controls the onset and
AN
resolution of acute inflammation through PGD2 and 15-deoxy∆12-14 PGJ2. Proc Natl Acad Sci U S A 2007;104:20979-84.
M
[52] Trivedi SG, Newson J, Rajakariar R, Jacques TS, Hannon R, Kanaoka Y, Eguchi N,
ED
Colville-Nash P, Gilroy DW. Essential role for hematopoietic prostaglandin D2 synthase in the control of delayed type hypersensitivity. Proc Natl Acad Sci U S A 2006;103:5179-84.
PT
[53] Murata T, Aritake K, Matsumoto S, Kamauchi S, Nakagawa T, Hori M, Momotani E, Urade
CE
Y, Ozaki H. Prostagladin D2 is a mast cell-derived antiangiogenic factor in lung carcinoma. Proc Natl Acad Sci U S A 2011;108:19802-7.
AC
[54] Pinzar E, Kanaoka Y, Inui T, Eguchi N, Urade Y, Hayaishi O. Prostaglandin D synthase gene is involved in the regulation of non-rapid eye movement sleep. Proc Natl Acad Sci U S A 2000;97:4903-4907. [55] Miwa Y, Takiuchi S, Kamide K, Yoshii M, Horio T, Tanaka C, Banno M, Miyata T, Sasaguri T, Kawano Y. Identification of gene polymorphism in lipocalin-type prostaglandin D synthase and its association with carotid atherosclerosis in Japanese hypertensive patients. Biochem
36
ACCEPTED MANUSCRIPT Biophys Res Commun 2004;322:428-33. [56] Ragolia L, Palaia T, Hall CE, Maesaka JK, Eguchi N, Urade Y. Accelerated glucose intolerance, nephropathy, and atherosclerosis in prostaglandin D2 synthase knock-out mice. J Biol Chem 2005;280:29946-55.
T
[57] Volat FE, Pointud JC, Pastel E, Morio B, Sion B, Hamard G, Guichardant M, Colas R,
IP
Lefrancois-Martinez AM, Martinez A. Depressed levels of prostaglandin F2α in mice lacking
CR
Akr1b7 increase basal adiposity and predispose to diet-induced obesity. Diabetes 2012;61:2796806.
US
[58] Yokoyama C, Yabuki T, Shimonishi M, Wada M, Hatae T, Ohkawara S, Takeda J, Kinoshita
AN
T, Okabe M, Tanabe T. Prostacyclin-deficient mice develop ischemic renal disorders, including nephrosclerosis and renal infarction. Circulation 2002;106:2397-403.
M
[59] Yu IS, Lin SR, Huang CC, Tseng HY, Huang PH, Shi GY, Wu HL, Tang CL, Chu PH, Wang
ED
LH, Wu KK, Lin SW. TXAS-deleted mice exhibit normal thrombopoiesis, defective hemostasis, and resistance to arachidonate-induced death. Blood 2004;104:135-42.
PT
[60] Zou H, Yuan C, Dong L, Sidhu RS, Hong YH, Kuklev DV, Smith WL. Human
CE
cyclooxygenase-1 activity and its responses to COX inhibitors are allosterically regulated by nonsubstrate fatty acids. J Lipid Res 2012;53:1336-47.
AC
[61] Smith T, Leipprandt J, DeWitt D. Purification and characterization of the human recombinant histidine-tagged prostaglandin endoperoxide H synthases-1 and -2. Arch Biochem Biophys 2000;375:195-200. [62] Kirkby NS, Chan MV, Zaiss AK, Garcia-Vaz E, Jiao J, Berglund LM, Verdu EF, AhmetajShala B, Wallace JL, Herschman HR, Gomez MF, Mitchell JA. Systematic study of constitutive cyclooxygenase-2 expression: Role of NF-kappaB and NFAT transcriptional pathways. Proc Natl
37
ACCEPTED MANUSCRIPT Acad Sci U S A 2016;113:434-9. [63] Frolich JC. Prostaglandin endoperoxide synthetase isoenzymes: the clinical relevance of selective inhibition. Ann Rheum Dis 1995;54:942-3. [64] Smith WL, Meade EA, DeWitt DL. Interactions of PGH synthase isozymes-1 and -2 with
T
NSAIDs. Ann N Y Acad Sci 1994;744:50-7.
IP
[65] Copeland RA, Williams JM, Giannaras J, Nurnberg S, Covington M, Pinto D, Pick S,
synthase. Proc Natl Acad Sci U S A 1994;91:11202-6.
CR
Trzaskos JM. Mechanism of selective inhibition of the inducible isoform of prostaglandin G/H
US
[66] Seibert K, Zhang Y, Leahy K, Hauser S, Masferrer J, Perkins W, Lee L, Isakson P.
AN
Pharmacological and biochemical demonstration of the role of cyclooxygenase 2 in inflammation and pain. Proc Natl Acad Sci U S A 1994;91:12013-7.
M
[67] Rome LH, Lands WE. Structural requirements for time-dependent inhibition of
ED
prostaglandin biosynthesis by anti-inflammatory drugs. Proc Natl Acad Sci U S A 1975;72:48635.
PT
[68] Blobaum AL, Marnett LJ. Structural and functional basis of cyclooxygenase inhibition. J
CE
Med Chem 2007;50:1425-41.
[69] Ouellet M, Percival MD. Effect of inhibitor time-dependency on selectivity towards
AC
cyclooxygenase isoforms. Biochem J 1995;306 ( Pt 1):247-51. [70] Gierse JK, McDonald JJ, Hauser SD, Rangwala SH, Koboldt CM, Seibert K. A single amino acid difference between cyclooxygenase-1 (COX-1) and -2 (COX-2) reverses the selectivity of COX-2 specific inhibitors. J Biol Chem 1996;271:15810-4. [71] Bertolini A, Ottani A, Sandrini M. Selective COX-2 inhibitors and dual acting antiinflammatory drugs: critical remarks. Curr Med Chem 2002;9:1033-43.
38
ACCEPTED MANUSCRIPT [72] Rouzer CA, Marnett LJ. Endocannabinoid oxygenation by cyclooxygenases, lipoxygenases, and cytochromes P450: cross-talk between the eicosanoid and endocannabinoid signaling pathways. Chem Rev 2011;111:5899-921. [73] Kulmacz RJ, van der Donk WA, Tsai AL. Comparison of the properties of prostaglandin H
T
synthase-1 and -2. Prog Lipid Res 2003;42:377-404.
IP
[74] Smith WL, Urade Y, Jakobsson PJ. Enzymes of the cyclooxygenase pathways of prostanoid
CR
biosynthesis. Chem Rev 2011;111:5821-65.
[75] Kang YJ, Mbonye UR, DeLong CJ, Wada M, Smith WL. Regulation of intracellular
US
cyclooxygenase levels by gene transcription and protein degradation. Prog Lipid Res
AN
2007;46:108-25.
[76] Picot D, Loll PJ, Garavito RM. The X-ray crystal structure of the membrane protein
M
prostaglandin H2 synthase-1. Nature 1994;367:243-9.
ED
[77] Miyamoto T, Ogino N, Yamamoto S, Hayaishi O. Purification of prostaglandin endoperoxide synthetase from bovine vesicular gland microsomes. J Biol Chem 1976;251:2629-
PT
36.
CE
[78] Dong L, Vecchio AJ, Sharma NP, Jurban BJ, Malkowski MG, Smith WL. Human cyclooxygenase-2 is a sequence homodimer that functions as a conformational heterodimer. J
AC
Biol Chem 2011;286:19035-46. [79] Asselin E, Drolet P, Fortier M. Cellular mechanisms involved during oxytocin-induced prostaglandin F2α production in endometrial epithelial cells in vitro: role of cyclooxygenase-2. Endocrinology 1997;138:4798-805. [80] Boerboom D, Sirois J. Molecular characterization of equine prostaglandin G/H synthase-2 and regulation of its messenger ribonucleic acid in preovulatory follicles. Endocrinology
39
ACCEPTED MANUSCRIPT 1998;139:1662-70. [81] Gierse JK, Hauser SD, Creely DP, Koboldt C, Rangwala SH, Isakson PC, Seibert K. Expression and selective inhibition of the constitutive and inducible forms of human cyclooxygenase. Biochem J 1995;305 ( Pt 2):479-84.
T
[82] DeWitt DL, el-Harith EA, Kraemer SA, Andrews MJ, Yao EF, Armstrong RL, Smith WL.
Biol Chem 1990;265:5192-8.
CR
IP
The aspirin and heme-binding sites of ovine and murine prostaglandin endoperoxide synthases. J
[83] Vecchio AJ, Simmons DM, Malkowski MG. Structural basis of fatty acid substrate binding
US
to cyclooxygenase-2. J Biol Chem 2010;285:22152-63.
AN
[84] Song JH, Sirois J, Houde A, Murphy BD. Cloning, developmental expression, and immunohistochemistry of cyclooxygenase 2 in the endometrium during embryo implantation and
M
gestation in the mink (Mustela vison). Endocrinology 1998;139:3629-36.
ED
[85] Guan Y, Chang M, Cho W, Zhang Y, Redha R, Davis L, Chang S, DuBois RN, Hao CM, Breyer M. Cloning, expression, and regulation of rabbit cyclooxygenase-2 in renal medullary
PT
interstitial cells. Am J Physiol 1997;273:F18-26.
CE
[86] Liu J, Seibold SA, Rieke CJ, Song I, Cukier RI, Smith WL. Prostaglandin endoperoxide H synthases: peroxidase hydroperoxide specificity and cyclooxygenase activation. J Biol Chem
AC
2007;282:18233-44.
[87] Johnson JL, Wimsatt J, Buckel SD, Dyer RD, Maddipati KR. Purification and characterization of prostaglandin H synthase-2 from sheep placental cotyledons. Arch Biochem Biophys 1995;324:26-34. [88] Feng L, Sun W, Xia Y, Tang WW, Chanmugam P, Soyoola E, Wilson CB, Hwang D. Cloning two isoforms of rat cyclooxygenase: differential regulation of their expression. Arch
40
ACCEPTED MANUSCRIPT Biochem Biophys 1993;307:361-8. [89] Kennedy BP, Chan CC, Culp SA, Cromlish WA. Cloning and expression of rat prostaglandin endoperoxide synthase (cyclooxygenase)-2 cDNA. Biochem Biophys Res Commun 1993;197:494-500.
T
[90] Xie WL, Chipman JG, Robertson DL, Erikson RL, Simmons DL. Expression of a mitogen-
IP
responsive gene encoding prostaglandin synthase is regulated by mRNA splicing. Proc Natl Acad
CR
Sci U S A 1991;88:2692-6.
[91] Grosser T, Yusuff S, Cheskis E, Pack MA, FitzGerald GA. Developmental expression of
US
functional cyclooxygenases in zebrafish. Proc Natl Acad Sci U S A 2002;99:8418-23.
AN
[92] Varvas K, Kurg R, Hansen K, Jarving R, Jarving I, Valmsen K, Lohelaid H, Samel N. Direct evidence of the cyclooxygenase pathway of prostaglandin synthesis in arthropods: genetic and
M
biochemical characterization of two crustacean cyclooxygenases. Insect Biochem Mol Biol
ED
2009;39:851-60.
[93] Valmsen K, Jarving I, Boeglin WE, Varvas K, Koljak R, Pehk T, Brash AR, Samel N. The
PT
origin of 15R-prostaglandins in the Caribbean coral Plexaura homomalla: molecular cloning and
CE
expression of a novel cyclooxygenase. Proc Natl Acad Sci U S A 2001;98:7700-5. [94] Varvas K, Kasvandik S, Hansen K, Jarving I, Morell I, Samel N. Structural and catalytic
AC
insights into the algal prostaglandin H synthase reveal atypical features of the first non-animal cyclooxygenase. Biochimica Et Biophysica Acta-Molecular and Cell Biology of Lipids 2013;1831:863-871. [95] Hamberg M, Samuelsson B. Detection and isolation of an endoperoxide intermediate in prostaglandin biosynthesis. Proc Natl Acad Sci U S A 1973;70:899-903. [96] Samuelsson B, Morgenstern R, Jakobsson PJ. Membrane prostaglandin E synthase-1: a
41
ACCEPTED MANUSCRIPT novel therapeutic target. Pharmacol Rev 2007;59:207-24. [97] Thoren S, Weinander R, Saha S, Jegerschold C, Pettersson PL, Samuelsson B, Hebert H, Hamberg M, Morgenstern R, Jakobsson PJ. Human microsomal prostaglandin E synthase-1: purification, functional characterization, and projection structure determination. J Biol Chem
T
2003;278:22199-209.
IP
[98] Thoren S, Jakobsson PJ. Coordinate up- and down-regulation of glutathione-dependent
CR
prostaglandin E synthase and cyclooxygenase-2 in A549 cells. Inhibition by NS-398 and leukotriene C4. Eur J Biochem 2000;267:6428-34.
US
[99] Murakami M, Nakatani Y, Tanioka T, Kudo I. Prostaglandin E synthase. Prostaglandins
AN
Other Lipid Mediat 2002;68-69:383-99.
[100] Yamamoto K, Suzuki M, Higashiura A, Aritake K, Urade Y, Uodome N, Hossain T,
M
Nakagawa A. New insights into the catalytic mechanism of Bombyx mori prostaglandin E
ED
synthase gained from structure-function analysis. Biochemical and Biophysical Research Communications 2013;440:762-767.
PT
[101] Yeh HC, Wang LH. Profiling of prostanoids in zebrafish embryonic development.
CE
Prostaglandins Leukot Essent Fatty Acids 2006;75:397-402. [102] Tanioka T, Nakatani Y, Semmyo N, Murakami M, Kudo I. Molecular identification of
AC
cytosolic prostaglandin E2 synthase that is functionally coupled with cyclooxygenase-1 in immediate prostaglandin E2 biosynthesis. J Biol Chem 2000;275:32775-82. [103] Bresell A, Weinander R, Lundqvist G, Raza H, Shimoji M, Sun TH, Balk L, Wiklund R, Eriksson J, Jansson C, Persson B, Jakobsson PJ, Morgenstern R. Bioinformatic and enzymatic characterization of the MAPEG superfamily. FEBS J 2005;272:1688-703. [104] Filion F, Bouchard N, Goff AK, Lussier JG, Sirois J. Molecular cloning and induction of
42
ACCEPTED MANUSCRIPT bovine prostaglandin E synthase by gonadotropins in ovarian follicles prior to ovulation in vivo. J Biol Chem 2001;276:34323-30. [105] Lazarus M, Kubata BK, Eguchi N, Fujitani Y, Urade Y, Hayaishi O. Biochemical characterization of mouse microsomal prostaglandin E synthase-1 and its colocalization with
T
cyclooxygenase-2 in peritoneal macrophages. Arch Biochem Biophys 2002;397:336-41.
and
up-regulation
of
inducible
rat
prostaglandin
CR
expression,
IP
[106] Mancini JA, Blood K, Guay J, Gordon R, Claveau D, Chan CC, Riendeau D. Cloning, E
synthase
during
lipopolysaccharide-induced pyresis and adjuvant-induced arthritis. J Biol Chem 2001;276:4469-
US
75.
AN
[107] Waclawik A, Rivero-Muller A, Blitek A, Kaczmarek MM, Brokken LJ, Watanabe K, Rahman NA, Ziecik AJ. Molecular cloning and spatiotemporal expression of prostaglandin F
M
synthase and microsomal prostaglandin E synthase-1 in porcine endometrium. Endocrinology
ED
2006;147:210-21.
[108] Watanabe K, Kurihara K, Suzuki T. Purification and characterization of membrane-bound
PT
prostaglandin E synthase from bovine heart. Biochim Biophys Acta 1999;1439:406-14.
CE
[109] Tanikawa N, Ohmiya Y, Ohkubo H, Hashimoto K, Kangawa K, Kojima M, Ito S, Watanabe K. Identification and characterization of a novel type of membrane-associated
AC
prostaglandin E synthase. Biochem Biophys Res Commun 2002;291:884-9. [110] Murakami M, Nakashima K, Kamei D, Masuda S, Ishikawa Y, Ishii T, Ohmiya Y, Watanabe K, Kudo I. Cellular prostaglandin E2 production by membrane-bound prostaglandin E synthase-2 via both cyclooxygenases-1 and -2. J Biol Chem 2003;278:37937-47. [111] Sjogren T, Nord J, Ek M, Johansson P, Liu G, Geschwindner S. Crystal structure of microsomal prostaglandin E2 synthase provides insight into diversity in the MAPEG superfamily.
43
ACCEPTED MANUSCRIPT Proc Natl Acad Sci U S A 2013;110:3806-11. [112] Cho H, Huang L, Hamza A, Gao D, Zhan CG, Tai HH. Role of glutamine 148 of human 15-hydroxyprostaglandin dehydrogenase in catalytic oxidation of prostaglandin E2. Bioorg Med Chem 2006;14:6486-91.
T
[113] Parent M, Madore E, MacLaren LA, Fortier MA. 15-Hydroxyprostaglandin dehydrogenase
IP
in the bovine endometrium during the oestrous cycle and early pregnancy. Reproduction
CR
2006;131:573-82.
[114] Bateman RL, Rauh D, Tavshanjian B, Shokat KM. Human carbonyl reductase 1 is an S-
US
nitrosoglutathione reductase. J Biol Chem 2008;283:35756-62.
AN
[115] Matsuo M, Ensor CM, Tai HH. Cloning and expression of the cDNA for mouse NAD(+)dependent 15-hydroxyprostaglandin dehydrogenase. Biochim Biophys Acta 1996;1309:21-4.
M
[116] Gonzalez B, Sapra A, Rivera H, Kaplan WD, Yam B, Forrest GL. Cloning and expression
ED
of the cDNA encoding rabbit liver carbonyl reductase. Gene 1995;154:297-8. [117] Zhang H, Matsuo M, Zhou H, Ensor CM, Tai HH. Cloning and expression of the cDNA for
PT
rat NAD+-dependent 15-hydroxyprostaglandin dehydrogenase. Gene 1997;188:41-4.
CE
[118] Wermuth B, Mader-Heinemann G, Ernst E. Cloning and expression of carbonyl reductase from rat testis. Eur J Biochem 1995;228:473-9.
carbonyl
AC
[119] Ghosh D, Sawicki M, Pletnev V, Erman M, Ohno S, Nakajin S, Duax WL. Porcine reductase.
structural
basis
for
a
functional
monomer
in
short
chain
dehydrogenases/reductases. J Biol Chem 2001;276:18457-63. [120] Tai HH, Ensor CM, Tong M, Zhou H, Yan F. Prostaglandin catabolizing enzymes. Prostaglandins Other Lipid Mediat 2002;68-69:483-93. [121] Cho H, Hamza A, Zhan CG, Tai HH. Key NAD+-binding residues in human 15-
44
ACCEPTED MANUSCRIPT hydroxyprostaglandin dehydrogenase. Arch Biochem Biophys 2005;433:447-53. [122] Urade Y, Fujimoto N, Ujihara M, Hayaishi O. Biochemical and immunological characterization of rat spleen prostaglandin D synthetase. J Biol Chem 1987;262:3820-5. [123] Urade Y, Watanabe K, Hayaishi O. Prostaglandin D, E, and F synthases. J Lipid Mediat
T
Cell Signal 1995;12:257-73.
IP
[124] Inoue T, Irikura D, Okazaki N, Kinugasa S, Matsumura H, Uodome N, Yamamoto M,
CR
Kumasaka T, Miyano M, Kai Y, Urade Y. Mechanism of metal activation of human hematopoietic prostaglandin D synthase. Nat Struct Biol 2003;10:291-6.
US
[125] Kanaoka Y, Fujimori K, Kikuno R, Sakaguchi Y, Urade Y, Hayaishi O. Structure and
AN
chromosomal localization of human and mouse genes for hematopoietic prostaglandin D synthase. Conservation of the ancestral genomic structure of sigma-class glutathione S-
M
transferase. Eur J Biochem 2000;267:3315-22.
ED
[126] Pinzar E, Miyano M, Kanaoka Y, Urade Y, Hayaishi O. Structural basis of hematopoietic
2000;275:31239-44.
PT
prostaglandin D synthase activity elucidated by site-directed mutagenesis. J Biol Chem
CE
[127] Shimizu T, Yamamoto S, Hayaishi O. Purification and properties of prostaglandin D synthetase from rat brain. J Biol Chem 1979;254:5222-8.
AC
[128] Hoffmann A, Conradt HS, Gross G, Nimtz M, Lottspeich F, Wurster U. Purification and chemical characterization of beta-trace protein from human cerebrospinal fluid: its identification as prostaglandin D synthase. J Neurochem 1993;61:451-6. [129] Watanabe K, Urade Y, Mader M, Murphy C, Hayaishi O. Identification of beta-trace as prostaglandin D synthase. Biochem Biophys Res Commun 1994;203:1110-6. [130] Gerena RL, Irikura D, Urade Y, Eguchi N, Chapman DA, Killian GJ. Identification of a
45
ACCEPTED MANUSCRIPT fertility-associated protein in bull seminal plasma as lipocalin-type prostaglandin D synthase. Biol Reprod 1998;58:826-33. [131] Zhou Y, Shaw N, Li Y, Zhao Y, Zhang R, Liu ZJ. Structure-function analysis of human lprostaglandin D synthase bound with fatty acid molecules. FASEB J 2010;24:4668-77.
T
[132] Fujimori K, Inui T, Uodome N, Kadoyama K, Aritake K, Urade Y. Zebrafish and chicken
IP
lipocalin-type prostaglandin D synthase homologues: Conservation of mammalian gene structure
CR
and binding ability for lipophilic molecules, and difference in expression profile and enzyme activity. Gene 2006;375:14-25.
US
[133] Kumasaka T, Aritake K, Ago H, Irikura D, Tsurumura T, Yamamoto M, Miyano M, Urade
AN
Y, Hayaishi O. Structural basis of the catalytic mechanism operating in open-closed conformers of lipocalin type prostaglandin D synthase. J Biol Chem 2009;284:22344-52.
M
[134] Madore E, Harvey N, Parent J, Chapdelaine P, Arosh JA, Fortier MA. An aldose reductase
ED
with 20α-hydroxysteroid dehydrogenase activity is most likely the enzyme responsible for the production of prostaglandin F2α in the bovine endometrium. J Biol Chem 2003;278:11205-12.
PT
[135] Kabututu Z, Manin M, Pointud JC, Maruyama T, Nagata N, Lambert S, Lefrancois-
CE
Martinez AM, Martinez A, Urade Y. Prostaglandin F2α synthase activities of aldo-keto reductase 1B1, 1B3 and 1B7. J Biochem 2009;145:161-8.
AC
[136] Kabututu Z, Martin SK, Nozaki T, Kawazu S, Okada T, Munday CJ, Duszenko M, Lazarus M, Thuita LW, Urade Y, Kubata BK. Prostaglandin production from arachidonic acid and evidence for a 9,11-endoperoxide prostaglandin H2 reductase in Leishmania. Int J Parasitol 2003;33:221-8. [137] Moriuchi H, Koda N, Okuda-Ashitaka E, Daiyasu H, Ogasawara K, Toh H, Ito S, Woodward
DF,
Watanabe
K.
Molecular
46
characterization
of
a
novel
type
of
ACCEPTED MANUSCRIPT prostamide/prostaglandin F synthase, belonging to the thioredoxin-like superfamily. J Biol Chem 2008;283:792-801. [138] Kubata BK, Duszenko M, Kabututu Z, Rawer M, Szallies A, Fujimori K, Inui T, Nozaki T, Yamashita K, Horii T, Urade Y, Hayaishi O. Identification of a novel prostaglandin F2α synthase
T
in Trypanosoma brucei. J Exp Med 2000;192:1327-38.
IP
[139] Kubata BK, Kabututu Z, Nozaki T, Munday CJ, Fukuzumi S, Ohkubo K, Lazarus M,
CR
Maruyama T, Martin SK, Duszenko M, Urade Y. A key role for old yellow enzyme in the
US
metabolism of drugs by Trypanosoma cruzi. J Exp Med 2002;196:1241-51. [140] Kuchinke W, Barski O, Watanabe K, Hayaishi O. A lung type prostaglandin F synthase is
AN
expressed in bovine liver: cDNA sequence and expression in E. coli. Biochem Biophys Res Commun 1992;183:1238-46.
M
[141] Suzuki-Yamamoto T, Nishizawa M, Fukui M, Okuda-Ashitaka E, Nakajima T, Ito S,
FEBS Lett 1999;462:335-40.
ED
Watanabe K. cDNA cloning, expression and characterization of human prostaglandin F synthase.
PT
[142] Schieber A, Frank RW, Ghisla S. Purification and properties of prostaglandin 9-
CE
ketoreductase from pig and human kidney. Identity with human carbonyl reductase. Eur J Biochem 1992;206:491-502.
AC
[143] Komoto J, Yamada T, Watanabe K, Takusagawa F. Crystal structure of human prostaglandin F synthase (AKR1C3). Biochemistry 2004;43:2188-98. [144] Schlegel BP, Jez JM, Penning TM. Mutagenesis of 3α-hydroxysteroid dehydrogenase reveals a "push-pull" mechanism for proton transfer in aldo-keto reductases. Biochemistry 1998;37:3538-48. [145] Matsuura K, Shiraishi H, Hara A, Sato K, Deyashiki Y, Ninomiya M, Sakai S.
47
ACCEPTED MANUSCRIPT Identification of a principal mRNA species for human 3α-hydroxysteroid dehydrogenase isoform (AKR1C3) that exhibits high prostaglandin D2 11-ketoreductase activity. J Biochem 1998;124:940-6. [146] Hara S, Miyata A, Yokoyama C, Inoue H, Brugger R, Lottspeich F, Ullrich V, Tanabe T.
T
Isolation and molecular cloning of prostacyclin synthase from bovine endothelial cells. J Biol
IP
Chem 1994;269:19897-903.
CR
[147] Cho SA, Rohn-Glowacki KJ, Jarrar YB, Yi M, Kim WY, Shin JG, Lee SJ. Analysis of genetic polymorphism and biochemical characterization of a functionally decreased variant in
US
prostacyclin synthase gene (CYP8A1) in humans. Arch Biochem Biophys 2015;569:10-8.
AN
[148] Choudhary D, Jansson I, Schenkman JB, Sarfarazi M, Stoilov I. Comparative expression profiling of 40 mouse cytochrome P450 genes in embryonic and adult tissues. Arch Biochem
M
Biophys 2003;414:91-100.
ED
[149] Gillio-Meina C, Phang SH, Mather JP, Knight BS, Kennedy TG. Expression patterns and role of prostaglandin-endoperoxide synthases, prostaglandin E synthases, prostacyclin synthase,
in
rat
2009;137:537-52.
endometrium
during
artificially-induced
decidualization.
Reproduction
CE
alpha
PT
prostacyclin receptor, peroxisome proliferator-activated receptor delta and retinoid x receptor
AC
[150] Hecker M, Ullrich V. On the mechanism of prostacyclin and thromboxane A2 biosynthesis. J Biol Chem 1989;264:141-50. [151] Li YC, Chiang CW, Yeh HC, Hsu PY, Whitby FG, Wang LH, Chan NL. Structures of prostacyclin synthase and its complexes with substrate analog and inhibitor reveal a ligandspecific heme conformation change. J Biol Chem 2008;283:2917-26. [152] Wang LH, Kulmacz RJ. Thromboxane synthase: structure and function of protein and
48
ACCEPTED MANUSCRIPT gene. Prostaglandins Other Lipid Mediat 2002;68-69:409-22. [153] Sadowitz PD, Setty BN, Stuart M. The platelet cyclooxygenase metabolite 12-L-hydroxy5, 8, 10-hepta-decatrienoic acid (HHT) may modulate primary hemostasis by stimulating prostacyclin production. Prostaglandins 1987;34:749-63.
T
[154] Hsu PY, Tsai AL, Kulmacz RJ, Wang LH. Expression, purification, and spectroscopic
IP
characterization of human thromboxane synthase. J Biol Chem 1999;274:762-9.
CR
[155] Zhang L, Chase MB, Shen RF. Molecular cloning and expression of murine thromboxane synthase. Biochem Biophys Res Commun 1993;194:741-8.
US
[156] Zhang L, Xiao H, Schultz RA, Shen RF. Genomic organization, chromosomal localization,
AN
and expression of the murine thromboxane synthase gene. Genomics 1997;45:519-28. [157] Tone Y, Miyata A, Hara S, Yukawa S, Tanabe T. Abundant expression of thromboxane
M
synthase in rat macrophages. FEBS Lett 1994;340:241-4.
ED
[158] Shen RF, Tai HH. Immunoaffinity purification and characterization of thromboxane synthase from porcine lung. J Biol Chem 1986;261:11592-9.
PT
[159] Ruan KH, Milfeld K, Kulmacz RJ, Wu KK. Comparison of the construction of a 3-D
CE
model for human thromboxane synthase using P450cam and BM-3 as templates: implications for the substrate binding pocket. Protein Eng 1994;7:1345-51.
AC
[160] Hsu PY, Tsai AL, Wang LH. Identification of thromboxane synthase amino acid residues involved in heme-propionate binding. Arch Biochem Biophys 2000;383:119-27. [161] Corey EJ, Schaaf TK, Huber W, Koelliker U, Weinshenker NM. Total Synthesis of Prostaglandins F2α and E2 as the Naturally Occuring Forms. J Am Chem Soc 1970;92:397-398. [162] Capper EA, Marshall LA. Mammalian phospholipases A2: mediators of inflammation, proliferation and apoptosis. Prog Lipid Res 2001;40:167-97.
49
ACCEPTED MANUSCRIPT [163] Jakobsson PJ, Thoren S, Morgenstern R, Samuelsson B. Identification of human prostaglandin E synthase: a microsomal, glutathione-dependent, inducible enzyme, constituting a potential novel drug target. Proc Natl Acad Sci U S A 1999;96:7220-5. [164] Chan BS, Endo S, Kanai N, Schuster VL. Identification of lactate as a driving force for
T
prostanoid transport by prostaglandin transporter PGT. Am J Physiol Renal Physiol
IP
2002;282:F1097-102.
CR
[165] Schuster VL, Chi Y, Lu R. The Prostaglandin Transporter: Eicosanoid Reuptake, Control of Signaling, and Development of High-Affinity Inhibitors as Drug Candidates. Trans Am Clin
US
Climatol Assoc 2015;126:248-57.
AN
[166] Kanai N, Lu R, Satriano JA, Bao Y, Wolkoff AW, Schuster VL. Identification and characterization of a prostaglandin transporter. Science 1995;268:866-9.
M
[167] Pucci ML, Bao Y, Chan B, Itoh S, Lu R, Copeland NG, Gilbert DJ, Jenkins NA, Schuster
ED
VL. Cloning of mouse prostaglandin transporter PGT cDNA: species-specific substrate affinities. Am J Physiol 1999;277:R734-41.
PT
[168] Lu R, Schuster VL. Molecular cloning of the gene for the human prostaglandin transporter
CE
hPGT: gene organization, promoter activity, and chromosomal localization. Biochem Biophys Res Commun 1998;246:805-12.
AC
[169] Lu R, Kanai N, Bao Y, Schuster VL. Cloning, in vitro expression, and tissue distribution of a human prostaglandin transporter cDNA(hPGT). J Clin Invest 1996;98:1142-9. [170] Miyazaki H, Sekine T, Endou H. The multispecific organic anion transporter family: properties and pharmacological significance. Trends Pharmacol Sci 2004;25:654-62. [171] Brash AR, Baertschi SW, Ingram CD, Harris TM. On non-cyclooxygenase prostaglandin synthesis in the sea whip coral, Plexaura homomalla: an 8(R)-lipoxygenase pathway leads to
50
ACCEPTED MANUSCRIPT formation of an alpha-ketol and a Racemic prostanoid. J Biol Chem 1987;262:15829-39. [172] Koljak R, Boutaud O, Shieh BH, Samel N, Brash AR. Identification of a naturally occurring peroxidase-lipoxygenase fusion protein. Science 1997;277:1994-6. [173] Weinheimer AJ, Spraggins RL. The occurrence of two new prostaglandin derivatives (15-
T
epi-PGA2 and its acetate, methyl ester) in the gorgonian Plexaura homomalla chemistry of
IP
coelenterates. XV. Tetrahedron Lett 1969;5185-8.
CR
[174] Schneider WP, Hamilton RD, Rhuland LE. Occurrence of esters of (15S)-prostaglandin A2 and E2 in coral. J Am Chem Soc 1972;94:2122-3.
US
[175] Light RJ, Samuelsson B. Identification of prostaglandins in the gorgonian, Plexaura
AN
homomalla. Eur J Biochem 1972;28:232-40.
[176] Varvas K, Järving I, Koljak R, Vahemets A, Pehk T, Müürisepp A-M, Lille Ü, Samel N. In
M
vitro biosynthesis of prostaglandins in the White Sea soft coral Gersemia fruticosa: Formation of
ED
optically active PGD2, PGE2, PGF2α and 15-keto-PGF2α from arachidonic acid. Tetrahedron Lett 1993;34:3643-3646.
PT
[177] Varvas K, Koljak R, Järving I, Pehk T, Samel N. Endoperoxide pathway in prostaglandin
CE
biosynthesis in the soft coral Gersemia fruticosa. Tetrahedron Lett 1994;35:8267-8270. [178] Parve O, Jarving I, Martin I, Metsala A, Vallikivi I, Aidnik M, Pehk T, Samel N. Lipase-
AC
catalysed acylation of prostanoids. Bioorg Med Chem Lett 1999;9:1853-8. [179] Sajiki J. Acid Treatment Increased Leukotriene B4 in The Red Alga, Gracilaria asiatica (= verrucosa). Fisheries Sci 1999;65:914-918. [180] Imbs AB, Vologodskaya AV, Nevshupova NV, Khotimchenko SV, Titlyanov EA. Response of prostaglandin content in the red alga Gracilaria verrucosa to season and solar irradiance. Phytochemistry 2001;58:1067-72.
51
ACCEPTED MANUSCRIPT [181] Dang TH, Lee HJ, Yoo ES, Hong J, Choi JS, Jung JH. The occurrence of 15-ketoprostaglandins in the red alga Gracilaria verrucosa. Arch Pharm Res 2010;33:1325-9. [182] Gregson RP, Marwood JF, Quinn RJ. The occurrence of prostaglandins PGE2 and PGF2α in a plant-the red alga Gracilaria lichenoides. Tetrahedron Lett 1979;20:4505-4506.
T
[183] Hsu BY, Tsao CY, Chiou TK, Hwang PA, Hwang DF. HPLC determination for
IP
prostaglandins from seaweed Gracilaria gigas. Food Control 2007;18:639-645.
CR
[184] Nylund GM, Weinberger F, Rempt M, Pohnert G. Metabolomic assessment of induced and activated chemical defence in the invasive red alga Gracilaria vermiculophylla. PLoS One
US
2011;6:e29359.
AN
[185] Rempt M, Weinberger F, Grosser K, Pohnert G. Conserved and species-specific oxylipin pathways in the wound-activated chemical defense of the noninvasive red alga Gracilaria
M
chilensis and the invasive Gracilaria vermiculophylla. Beilstein J Org Chem 2012;8:283-9.
ED
[186] Kanamoto H, Takemura M, Ohyama K. Identification of a cyclooxygenase gene from the red alga Gracilaria vermiculophylla and bioconversion of arachidonic acid to PGF2α in
PT
engineered Escherichia coli. Appl Microbiol Biotechnol 2011;91:1121-9.
CE
[187] Guder JC, Buchhaupt M, Huth I, Hannappel A, Ferreiros N, Geisslinger G, Schrader J. Biotechnological approach towards a highly efficient production of natural prostaglandins.
AC
Biotechnol Lett 2014;36:2193-8. [188] Noverr MC, Phare SM, Toews GB, Coffey MJ, Huffnagle GB. Pathogenic yeasts Cryptococcus neoformans and Candida albicans produce immunomodulatory prostaglandins. Infect Immun 2001;69:2957-63. [189] Grozer Z, Toth A, Toth R, Kecskemeti A, Vagvolgyi C, Nosanchuk JD, Szekeres A, Gacser A. Candida parapsilosis produces prostaglandins from exogenous arachidonic acid and OLE2 is
52
ACCEPTED MANUSCRIPT not required for their synthesis. Virulence 2015;6:85-92. [190] Erb-Downward JR, Noverr MC. Characterization of prostaglandin E2 production by Candida albicans. Infect Immun 2007;75:3498-505. [191] Erb-Downward JR, Noggle RM, Williamson PR, Huffnagle GB. The role of laccase in
T
prostaglandin production by Cryptococcus neoformans. Mol Microbiol 2008;68:1428-37.
IP
[192] Broadway N. Recombinant protein expression: vector-host systems. Mater Methods
CR
2012;2:123.
[193] Kukk K, Jarving R, Samel N. Purification and characterization of the recombinant human
US
prostaglandin H synthase-2 expressed in Pichia pastoris. Protein Expr Purif 2012;83:182-9.
AN
[194] Macauley-Patrick S, Fazenda ML, McNeil B, Harvey LM. Heterologous protein production using the Pichia pastoris expression system. Yeast 2005;22:249-270.
M
[195] Kukk K, Samel N. Enhanced expression of human prostaglandin H synthase-2 in the yeast
ED
Pichia pastoris and removal of the C-terminal tag with bovine carboxypeptidase A. J Biotechnol 2016;231:224-31.
PT
[196] Shyue SK, Tsai MJ, Liou JY, Willerson JT, Wu KK. Selective augmentation of prostacyclin
2001;103:2090-5.
CE
production by combined prostacyclin synthase and cyclooxygenase-1 gene transfer. Circulation
AC
[197] Kim WI, Choi KA, Do HS, Yu YG. Expression and purification of human mPGES-1 in E. coli and identification of inhibitory compounds from a drug-library. BMB Rep 2008;41:808-13. [198] Mohamed ME, Lazarus CM. Prostanoid production in Saccharomyces cerevisiae provides a novel assay for nonsteroidal anti-inflammatory drugs. FEMS Yeast Res 2009;9:420-7. [199] Gong Y, Wan X, Jiang M, Hu C, Hu H, Huang F. Metabolic engineering of microorganisms to produce omega-3 very long-chain polyunsaturated fatty acids. Prog Lipid Res 2014;56:19-35.
53
ACCEPTED MANUSCRIPT [200] Tavares S, Grotkjaer T, Obsen T, Haslam RP, Napier JA, Gunnarsson N. Metabolic engineering of Saccharomyces cerevisiae for production of eicosapentaenoic acid, using a novel delta-5-Desaturase from Paramecium tetraurelia. Appl Environ Microbiol 2011;77:1854-61. [201] Sakuradani E, Ando A, Shimizu S, Ogawa J. Metabolic engineering for the production of
T
polyunsaturated fatty acids by oleaginous fungus Mortierella alpina 1S-4. J Biosci Bioeng
IP
2013;116:417-22.
CR
[202] Hao G, Chen H, Gu Z, Zhang H, Chen W, Chen YQ. Metabolic engineering of Mortierella alpina for arachidonic acid production with glycerol as carbon source. Microb Cell Fact
US
2015;14:205.
AN
[203] Hao G, Chen H, Gu Z, Zhang H, Chen W, Chen YQ. Metabolic engineering of Mortierella
Environ Microbiol 2016;82:3280-8.
M
alpina for enhanced arachidonic acid production through the NADPH-supplying strategy. Appl
ED
[204] Xue Z, Sharpe PL, Hong SP, Yadav NS, Xie D, Short DR, Damude HG, Rupert RA, Seip JE, Wang J, Pollak DW, Bostick MW, Bosak MD, Macool DJ, Hollerbach DH, Zhang H, Arcilla
PT
DM, Bledsoe SA, Croker K, McCord EF, Tyreus BD, Jackson EN, Zhu Q. Production of omega-
AC
2013;31:734-40.
CE
3 eicosapentaenoic acid by metabolic engineering of Yarrowia lipolytica. Nat Biotechnol
54
ACCEPTED MANUSCRIPT Figure legends
Fig. 1. Nomenclature of PGs. (A) PGs are assigned as the suffix of PG using a letter from A to K based on the position of the substituents on the cyclopentane ring. TXA or TXB is assigned as a
IP
T
six-membered ether-containing ring. R1 and R2 indicate the carbon chains. (B) PGX1, PGX2 and
CR
PGX3 are assigned as the subscript number of PGX using the number of double bonds in the carbon chains, and they are derived from DGLA, AA, and EPA, respectively. ‘X’ indicate
US
several types of cyclopentane rings. R1 and R2 show the carboxylic (upper chemical structure)
AN
and hydro(pero)xyl (lower chemical structure) groups, respectively. Fig. 2. Synthesis pathway of diverse PGs from PGH2. PGE2, 15-keto-PGE2, PGD2, PGF2α, PGI2,
M
and TXA2 are formed by PG synthases (solid line). PGA2, PGB2, PGC2, PGJ2,
∆12,14
15-deoxy-
ED
PGJ2, 6-keto-PGF1α, and TXB2 are formed by non-enzymatic reactions (dotted line).
PT
Fig. 3. Proposed reaction mechanisms and 3D-structures of active sites in PG synthases. (A) PGHS (PDB No. 1U67). (B) PGES (PDB No. 4AL1). (C) 15-HPGD (PDB No. 2GDZ). (D) H-
CE
PGDS (PDB No. 1PD2). (E) L-PGDS (PDB No. 3O19). (F) PGFS-1 (PDB No. 1VBJ). (G)
AC
PGFS-2 (PDB No. 1RY0). (H) PGIS (PDB No. 2IAG). (I) TXAS (Molecular model). Internal molecules (turquoise blue) indicate ligands. Red color indicates catalytic residues. Purple color indicates residues involved in the abstraction of electron donor. Gold and gray colors indicate residues involved in the cyclization for PGH2 and NSAIDs-binding site of PGHS, respectively. Green color indicates residues involved in the interaction with co-factors. Dark-blue color indicates residues involved in the formation of hydrogen bonds. Pink color indicates residues involved in the formation of catalytic triad or tetrad. Blue color indicates substrate-binding site
55
ACCEPTED MANUSCRIPT residues. Orange color indicates residues involved in the interaction with metal. Lavender-purple color indicates residues involved in the activation of thiol group. Dark-green color indicates residues involved in release of PGD2. Sky-blue color indicates residues involved in interaction with heme. 3D-structures of PG synthases are redrawn using Discovery Studio 4.0 (Accerlys,
IP
T
San Diego, CA, USA) based on their crystal structures.
CR
Fig. 4. Mammalian, algal, coral, and fungal biosynthesis pathways of PGs derived from AA released from phospholipids by phospholipase A2. Solid lines indicate experimentally confirmed
US
pathways, and dotted lines indicate putative pathways. NE, non-enzymatic reactions.
AN
Fig. 5. Proposed metabolically engineered pathway for synthesis of C20 unsaturated fatty acid. PGs can be synthesized from three types of substrates including DGLA (blue), AA (red), and
M
EPA (purple) by PG-converting enzymes. LA, linoleic acid (C18:2∆9Z, 12Z); ALA, α-linolenic acid
ED
(C18:3∆9Z, 12Z, 15Z); EDA, eicosadienoic acid (C20:2∆11Z, 14Z); ETrA, eicosatrienoic acid (C20:3∆11Z, ); DGLA, dihomo-γ-linolenic acid (C20:3∆8Z,11Z,14Z); ETA, eicosatetraenoic acid (C20:4∆8Z,
14Z, 17Z
); AA, arachidonic acid (C20:4∆5Z, 8Z, 11Z, 14Z); EPA, eicosapentaenoic acid (C20:5∆5Z, 8Z,
PT
11Z, 14Z, 17Z
11Z, 14Z, 17Z
AC
CE
)
56
ACCEPTED MANUSCRIPT
US
CR
IP
T
A
AC
CE
PT
ED
M
AN
B
Fig. 1
57
AC
CE
PT
ED
M
AN
US
CR
IP
T
ACCEPTED MANUSCRIPT
Fig. 2
58
CR IP T AC
CE
PT
ED
M AN
US
A
Fig. 3-continued
59
CR IP T US AC
CE
PT
ED
M AN
B
Fig. 3-continued
60
CR IP T AC
CE
PT
ED
M AN
US
C
Fig. 3-continued
61
CR IP T AC
CE
PT
ED
M AN
US
D
Fig. 3-continued
62
CR IP T AC
CE
PT
ED
M AN
US
E
Fig. 3-continued
63
CR IP T AC
CE
PT
ED
M AN
US
F
Fig. 3-continued 64
CR IP T AC
CE
PT
ED
M AN
US
G
Fig. 3-continued 65
CR IP T AC
CE
PT
ED
M AN
US
H
Fig. 3-continued 66
ED
PT
CE
AC
CR IP T
US
M AN
I
Fig. 3
67
AC
CE
PT
ED
M
AN
US
CR
IP
T
ACCEPTED MANUSCRIPT
Fig. 4
68
Fig. 5
69
ED
PT
CE
AC
CR IP T
US
M AN
ACCEPTED MANUSCRIPT Table 1. Functions of prostaglandins. Structure
Receptor
Functions
Ref.
Prostaglandin H2 (PGH2)
−
Precursor of other prostaglandins
[3]
Prostaglandin E2 (PGE2)
EP1, EP2, EP3, EP4
Pain response, Maturation for ovulation, Fertilization
[3, 15]
15-Ketoprostaglandin E2 (15-Keto-PGE2)
PPAR-γ
Agonist, Induces adipogenesis
Prostaglandin D2 (PGD2)
DP1, DP2
Allergic asthma, Chemotaxis
Prostaglandin F2α (PGF2α)
PGF
CR
US
[40]
[30, 31]
[32, 33]
IP1, IP2
Vasodilation, Declumping
[34, 35]
TPα , TPβ
Vasoconstriction, Platelet aggregation
[38, 39]
M
AN
Contraction, Parturition,
AC
CE
PT
ED
Prostaglandin I2 (PGI2)
Thromboxane A2 (TXA2)
IP
T
Prostaglandin
70
CR IP T
Table 2. Biochemical properties of prostaglandin synthases.
PGHS-1
Bos taurus Danio rerio Homo sapiens Ovis aries (POX) Mus musculus Rattus norvegicus Gracilaria vermiculophylla Bos taurus Caprella sp. Cavia porcellus Danio rerio Equus caballus Gallus gallus Gammarus sp. Homo sapiens Mus musculus Neovison vison Oryctolagus cuniculus Ovis aries Rattus norvegicus Gersemia fruticosa Plexaura homomalla Bombyx mori Danio rerio Homo sapiens
Substrate
AA − AA 15-HPETE AA AA AA AA AA AA − AA AA AA AA AA AA AA AA AA AA AA PGH2 PGH2 PGH2
PGES
AC
CE
PT
ED
PGHS-2
Typical organism
cPGES
mPGES-1
mPGES-2
Km
kcat
(µM )
(s )
Temp. o ( C)
pH
Mw (Da)
Quaternary structure
Ref.
− − 37 37 37 − 25 − 25 − − − − 25 25 37 − − − − 25 25
− − 8.0 8.0 8.0 − 8.0 − 8.0 − − − − 8.0 7.2 – 8.0 8.0 − − − − 8.0 8.0
− − Dimer Dimer Dimer Dimer Tetramer − − − − − Dimer − Dimer Dimer − − Dimer − − −
[79] [91] [60] [86] [82] [88] [94] [205] [92] [206] [91] [80] [90] [92] [81] [83] [84] [85] [87] [89] [23] [93]
25 −
8.0 −
Monomer −
[100] [101]
8.0
70,000 68,963 73,000 70,000 70,000 70,000 63,500 72,000 68,000 69,000 68,673 69,000 70,000 68,000 70,000 70,000 69,000 69,000 72,000 72,000 68,000 68,000 24,000 17,149 26,000
Monomer
[42]
− − 8.0
16,000 16,458 17,500
− − Trimer
Accession no.
Specific activity (µmol/min/mg)
O62664 Q8JH44 P23219 P05979 P22437 Q63921 I6VVK9 O62698 D2W902 P70682 Q8JH43 O19183 P27607 D2W903 P35354 Q05769 O62725 O02768 P79208 P35355 Q9GPF4 Q962I8 Q5CCJ4 Q5IHX6 Q15185
− − 19 34 0.3 − 124 − − − − − − − 12.2 − − − 30.8 − − − 0.07 − 1.9
− − 5.1 42 − − 21 − − − − − − − 8.7 5.1 − − 2.1 − − − − − 14
120 − − 92 − − − − − − − − 27 − − − − − − − − 0.8
24
− − 170
− − 160
− − 50
− − 37
US
PGHS
Subtype
M AN
Enzyme
−1
−1
− −
Bos taurus Danio rerio Homo sapiens
− PGH2 PGH2
Q95L14 Q5IHX7 O14684
Mus musculus
PGH2
Q9JM51
−
130
10
24
8.0
17,000
−
[104] [101] [97] [103]
Rattus norvegicus
PGH2
Q9JHF3
−
−
−
−
7.0
17,000
−
[102]
Sus scrofa Bos taurus
− PGH2
Q2TJZ7 Q66LN0
− 0.83
− 24
− 0.43
− 24
− 6.5
17,300 33,000
− Dimer
[108]
71
[107]
15-HPGD-2
−
−
−
−
−
41,914
−
[109]
Q9N0A4 Q8BWM0 Q309F3
3.3 − 3.3
28 − −
1.8 − −
24 − 25
6.5 − 9.0
33,107 44,000 29,000
Dimer − Dimer
[109] [110] [113]
Homo sapiens
PGE2
P15428
2.8
3.4
50
37
7.5
29,000
Dimer
[112]
Mus musculus Rattus norvegicus
−
− −
− −
− −
− 37
− 9.0
28,775 29,000
Dimer Dimer
[115] [117]
P16152
−
309
P48758 P47844 P47727
− − −
− − 0.0002
− PGH2
Q28960 O60760
− 30
− 200
PGH2
Q9JHF7
28
200
−
25
8.0
23,226
Dimer
[125]
Rattus norvegicus
PGH2
O35543
33
200
−
25
8.0
23.297
Dimer
[125]
Schistosoma mansoni Bos taurus
PGH2 PGH2
P09792 O02853
1 0.005
0.31 −
− −
25 −
7.4 −
28,000 26,000
− Monomer
[22] [130]
Danio rerio
PGH2
Q8QGV4
−
−
−
−
−
20,875
−
[101]
Homo sapiens
PGH2
P41222
9.3
14
26
25
8.0
29,000
Monomer
[131]
Gallus gallus
PGH2
Q8QFM7
12
−
−
25
8.0
21,000
Monomer
[132]
Mus musculus
PGH2
O09114
434
−
−
25
8.0
21,000
Monomer
[132]
Bos taurus Homo sapiens Leishmania major
PGH2 PGH2 PGH2
P16116 P15121 P22045
0.024 0.026 0.27
7.1 1.9 15
0.014 0.016 0.14
25 37 37
7.5 7.0 7.0
36,000 36,000 34,000
− Monomer −
[134] [135] [136]
Mus musculus
Sus scrofa
PGH2 PGH2 PGH2 PGH2
Q9DB60 P45376 P21300 A9CQL8
0.69 0.053 0.044 0.69
7.6 9.3 3.8 7.0
0.25 0.032 0.026 0.25
24 37 37 24
7.0 7.0 7.0 7.0
21,669 36,000 36,000 20,000
− Monomer Monomer Dimer
[137] [135] [135] [137]
Q2TJA5 Q9GV41
− 2.0
− 1.3
− 1.30
− 37
− 7.0
36,000 33,000
− −
[107] [138]
Sus scrofa Homo sapiens
PGFS-1
AC
PGFS
CE
L-PGDS
PT
Mus musculus
ED
H-PGDS
PGIS
+
NAD PGE2
Q8VCC1 O08699
− − PGE2
Homo sapiens Mus musculus Oryctolagus cuniculus Rattus norvegicus
PGDS
CR IP T
Q9H7Z7
PGH2 − PGE2
US
15-HPGD-1
PGH2
Macaca fascicularis Mus musculus Bos taurus
M AN
15-HPGD
Homo sapiens
25
37
8.0
30,000
Monomer
[114, 207]
− − 0.03
− − 30
− − 7.0
30,000 30,000 30,000
− − Monomer
[208] [116] [118]
− −
45 25
5.5 8.0
31,000 23,343
Monomer Dimer
[119] [125]
Trypanosoma brucei
− PGH2
Trypanosoma cruzi
PGH2
Q8I6L9
0.77
5.0
0.54
37
7.0
42,000
−
[139]
PGFS-2
Bos taurus Homo sapiens
PGD2 PGD2
P52897 P42330
− 2.0
− 3.4
− 1.2
− 37
− 10.0
37,000 36,000
− −
[140] [141]
PGFS-3
Sus scrofa
PGE2
Q28960
0.02
0.16
−
25
6.5
32,000
Monomer
[142]
Bos taurus
PGH2
Q29626
2.0
9.0
2.45
24
7.4
52,000
−
[146]
Danio rerio
PGH2
A9LLA5
−
−
−
−
−
55,240
−
[101]
PGIS
72
− − PGH2
CR IP T
Mus musculus Rattus norvegicus Sus scrofa
9.5 − − −
P24557
12
20
0.02
23
7.5
56,000
Monomer
[154]
P36423 P49430 P47787
− − 0.23
− − 12
− − −
− − 30
− − 7.5
58,220 60,000 60,000
− − −
[155, 156] [157] [158]
US
PGH2
534 − − −
M AN
Homo sapiens
Q16647 O35074 Q62969 Q6TGT4
CE
PT
ED
TXAS
U46619 − − PGH2
AC
TXAS
Homo sapiens Mus musculus Rattus norvegicus Danio rerio
73
− − − −
23 − − −
7.5 − − −
56,000 57,000 56,500 62,790
Monomer − Monomer −
[147] [148] [149] [101]
CR IP T
Table 3. Structural information of prostaglandin synthases. PDB no.
Co-factor
Catalytic residue
PGHS
1U67
Heme
Tyr385
Substrate-binding residues
US
Enzyme
Residue function
Arg120
Opening the active site
207
388
Heme liganding
348
533
Hydrogen abstraction
349
387
Cyclization
49
126
L-PGDS
PGFS-1
PGFS-2
PGFS-3 PGIS TXAS
3O19
Ser
NAD+ or NADP+
ED
1PD2
GSH
2+
GSH and Mg
PT
H-PGDS
2GDZ
127
−
CE
15-HPGD
4AL1
1VBJ
AC
PGES
M AN
His , His
1RY0
1N5D
2IAG −
NADPH
NADPH
Ser138
Tyr , Gly
Val
, Trp
Asp , Arg
Proton abstraction
Arg73, Asn17, Glu77, His113, Tyr117, Arg126
GSH coordination
Tyr151, Lys155
Formation of catalytic triad
Gln
148
Formation of hydrogen bonds
11
74
91
182
Thr , Ile , Asn , Cys , Val 8
Tyr
14
Arg , Trp
104
96
96
97
Lys112, Cys156, Lys198 Cys
45
67
54
111
81
47
77
Trp , His
Tyr 117
Interaction with Mg2+ Substrate binding
Interaction with cofactor
52
55
Cofactor binding site
Involved in release of PGD2
Asp , Lys
His
, Thr
Activation of the thiol group of Cys65
Ser , Thr , Ser
110
188
GSH transfer
Asp , Asp , Asp 65
186
Formation of catalytic tetrad
50
84
Tyr , His
Asp , Lys
194
106
Interaction with cofactor Formation of catalytic tetrad
NADPH and GSH Heme Heme
Tyr
441
Cys
480
Cys
Asp
, Gln
140
Interaction with cofactor
447
Ala
Heme liganding
110
413
133
137
478
Asn , Arg , Arg Trp
, Arg
Arg86, Phe127, Met237, Leu521
74
Interaction with A−ring of heme Interaction with D−ring of heme Stabilization of binding pocket