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The contribution of Scottish scientists to the emergence of nitric oxide as an important biological molecule
Abstracts / Nitric Oxide 27 (2012) S2–S50
cence analyses identified the location of eNOS and GSNOR in corporal tissue. eNOS and nNOS were S-nitrosylated in unstimulated penises of wild type mice. CCNES resulted in a time-dependent increase in eNOS S-nitrosylation with peak eNOS S-nitrosylation observed during detumescence. S-nitrosylated nNOS levels were unchanged. eNOS and GSNO-R co-localize to the endothelium of the corpus cavernosum. SNitrosylated eNOS levels were elevated in the penis of GSNOR / mice compared to C57BL6 animals. Intracorporal pressure measurements obtained during CCNES demonstrate GSNOR+/ and GSNOR / animals cannot maintain tumescence. Results suggest that eNOS Snitrosylation/denitrosylation is an important mechanism regulating eNOS activity during erectile function and GSNO-R is a key enzyme involved in the denitrosylation of eNOS. The increase in eNOS S-Nitrosylation (inactivation) observed with tumescence may begin a cycle leading to detumescence. http://dx.doi.org/10.1016/j.niox.2012.04.079
P-22
Abstract Withdrawn. http://dx.doi.org/10.1016/j.niox.2012.04.080
P-23
Abstract Withdrawn http://dx.doi.org/10.1016/j.niox.2012.04.081
P-24 Abstract Withdrawn http://dx.doi.org/10.1016/j.niox.2012.04.082
S23
Molecular and post-translational regulation of NOS enzymes P-26 Design, synthesis and evaluation of a novel inhibitor targeted at the NADPH site of nitric oxide synthase Yun Li a, Bogdan Tarus b, Etienne Henry c, Booma Ramassamy a, Hamid Dhimane a, Chantal Dessy d, Eric Deprez c, Anny SlamaSchwok b, Jean-Luc Boucher a a CNRS UMR 8601, University Paris Descartes, Paris, France, b UR 892, INRA, Jouy en Josas, France, c CNRS UMR 8113, Institut d’Alembert, ENS-Cachan, Cachan, France, d UCL Medical Sector, Brussels, Belgium In mammals, NO is a signalling mediator that exerts a wide range of key physiological functions. The biological activities of NO are closely linked to the NO-synthase isoform involved in its synthesis and deregulation of its biosynthesis leads to several pathologies. Taking account of the crystallographic structures and of the critical role of the heme in catalysis, much effort has been dedicated to the design of inhibitors targeting the heme site. With the exception of diphenyliodonium and its close analogues, no chemical compound specifically targets the NADPH site of the reductase domain of NOS. In recent studies, we have characterized a NADPH analogue called nanotrigger NT1 that binds the NADPH site of the rductase domain of NOS. Following photoactivation, the terminal amine group of excited NT1⁄ injected electrons to the FAD acceptor of NOS, thereby initiating the electron flow and catalysis. Based on molecular modelling studies, we designed and synthesized a novel prototype of NOS inhibitor, called nanoshutter (NS1) bearing a phosphorylated adenosine moiety as recognition motif of the NADPH site linked by an alkyl chain to a new chromophore. NS1 inhibited the formation of NO catalyzed by neuronal NOS in a dose-dependent manner. This inhibition was competitive and reversible with NADPH, in agreement with NS1 being addressed to the reductase domain of nNOS. Further work is in progress to improve the selectivity and affinity of this new class of NOS inhibitors and to explore the pharmacological properties of NS1. The photochemical properties of NS1 are also under investigation. http://dx.doi.org/10.1016/j.niox.2012.04.084
P-25 The contribution of Scottish scientists to the emergence of nitric oxide as an important biological molecule Anthony Butler University of St. Andrews, St. Andrews, UK The discovery that nitric oxide (NO) plays an important role in animal and plant physiology is one of the most exciting developments in science during the latter part of the twentieth century. Although not major players in the drama, a number of Scottish scientists played minor parts in the work that led up to the emergence of nitric oxide. Lauder Brunton, a physician at Edinburgh Royal Infirmary, first used organic nitrites to control blood pressure in humans. Sodium nitroprusside (SNP) was first made by the St. Andrews chemist Lyon Playfair and S-nitrothiols were first described by the Scottish chemist Alexander Macbeth. These historical trivia will be described in more detail in the poster. http://dx.doi.org/10.1016/j.niox.2012.04.083
P-27 Electron transfer in bacterial NO-synthases: Role of tetrahydrobiopterin Jérôme Santolini, Albane Brunel, Pierre Dorlet Laboratoire Stress Oxydant et Détoxication, UMR 8221 CNRS-Univ. Paris Sud-CEA, CEA Saclay Bât 532, Gif-sur-Yvette, France NO-synthases (NOSs) produce NO by a two-oxidation reaction that sequentially converts arginine (L-Arg) into NOHA and citrulline, with NO as byproduct. Like cytochromes P450, the molecular mechanism of oxygen activation by NOS relies on the sequential transfer of two electrons and two protons, leading to the formation of a Compound-I like species that will eventually achieve L-Arg oxidation. In the last ten years, intense investigations on electron transfer in NOS have revealed that the second electron donor is a pterin cofactor, H4B. However, several questions concerning electron transfer in the NO-producing step (NOHA oxidation) remains to be addressed: the number of electron transfer (one vs two), the nature of the oxidative
cence analyses identified the location of eNOS and GSNOR in corporal tissue. eNOS and nNOS were S-nitrosylated in unstimulated penises of wild type mice. CCNES resulted in a time-dependent increase in eNOS S-nitrosylation with peak eNOS S-nitrosylation observed during detumescence. S-nitrosylated nNOS levels were unchanged. eNOS and GSNO-R co-localize to the endothelium of the corpus cavernosum. SNitrosylated eNOS levels were elevated in the penis of GSNOR / mice compared to C57BL6 animals. Intracorporal pressure measurements obtained during CCNES demonstrate GSNOR+/ and GSNOR / animals cannot maintain tumescence. Results suggest that eNOS Snitrosylation/denitrosylation is an important mechanism regulating eNOS activity during erectile function and GSNO-R is a key enzyme involved in the denitrosylation of eNOS. The increase in eNOS S-Nitrosylation (inactivation) observed with tumescence may begin a cycle leading to detumescence. http://dx.doi.org/10.1016/j.niox.2012.04.079
P-22
Abstract Withdrawn. http://dx.doi.org/10.1016/j.niox.2012.04.080
P-23
Abstract Withdrawn http://dx.doi.org/10.1016/j.niox.2012.04.081
P-24 Abstract Withdrawn http://dx.doi.org/10.1016/j.niox.2012.04.082
S23
Molecular and post-translational regulation of NOS enzymes P-26 Design, synthesis and evaluation of a novel inhibitor targeted at the NADPH site of nitric oxide synthase Yun Li a, Bogdan Tarus b, Etienne Henry c, Booma Ramassamy a, Hamid Dhimane a, Chantal Dessy d, Eric Deprez c, Anny SlamaSchwok b, Jean-Luc Boucher a a CNRS UMR 8601, University Paris Descartes, Paris, France, b UR 892, INRA, Jouy en Josas, France, c CNRS UMR 8113, Institut d’Alembert, ENS-Cachan, Cachan, France, d UCL Medical Sector, Brussels, Belgium In mammals, NO is a signalling mediator that exerts a wide range of key physiological functions. The biological activities of NO are closely linked to the NO-synthase isoform involved in its synthesis and deregulation of its biosynthesis leads to several pathologies. Taking account of the crystallographic structures and of the critical role of the heme in catalysis, much effort has been dedicated to the design of inhibitors targeting the heme site. With the exception of diphenyliodonium and its close analogues, no chemical compound specifically targets the NADPH site of the reductase domain of NOS. In recent studies, we have characterized a NADPH analogue called nanotrigger NT1 that binds the NADPH site of the rductase domain of NOS. Following photoactivation, the terminal amine group of excited NT1⁄ injected electrons to the FAD acceptor of NOS, thereby initiating the electron flow and catalysis. Based on molecular modelling studies, we designed and synthesized a novel prototype of NOS inhibitor, called nanoshutter (NS1) bearing a phosphorylated adenosine moiety as recognition motif of the NADPH site linked by an alkyl chain to a new chromophore. NS1 inhibited the formation of NO catalyzed by neuronal NOS in a dose-dependent manner. This inhibition was competitive and reversible with NADPH, in agreement with NS1 being addressed to the reductase domain of nNOS. Further work is in progress to improve the selectivity and affinity of this new class of NOS inhibitors and to explore the pharmacological properties of NS1. The photochemical properties of NS1 are also under investigation. http://dx.doi.org/10.1016/j.niox.2012.04.084
P-25 The contribution of Scottish scientists to the emergence of nitric oxide as an important biological molecule Anthony Butler University of St. Andrews, St. Andrews, UK The discovery that nitric oxide (NO) plays an important role in animal and plant physiology is one of the most exciting developments in science during the latter part of the twentieth century. Although not major players in the drama, a number of Scottish scientists played minor parts in the work that led up to the emergence of nitric oxide. Lauder Brunton, a physician at Edinburgh Royal Infirmary, first used organic nitrites to control blood pressure in humans. Sodium nitroprusside (SNP) was first made by the St. Andrews chemist Lyon Playfair and S-nitrothiols were first described by the Scottish chemist Alexander Macbeth. These historical trivia will be described in more detail in the poster. http://dx.doi.org/10.1016/j.niox.2012.04.083
P-27 Electron transfer in bacterial NO-synthases: Role of tetrahydrobiopterin Jérôme Santolini, Albane Brunel, Pierre Dorlet Laboratoire Stress Oxydant et Détoxication, UMR 8221 CNRS-Univ. Paris Sud-CEA, CEA Saclay Bât 532, Gif-sur-Yvette, France NO-synthases (NOSs) produce NO by a two-oxidation reaction that sequentially converts arginine (L-Arg) into NOHA and citrulline, with NO as byproduct. Like cytochromes P450, the molecular mechanism of oxygen activation by NOS relies on the sequential transfer of two electrons and two protons, leading to the formation of a Compound-I like species that will eventually achieve L-Arg oxidation. In the last ten years, intense investigations on electron transfer in NOS have revealed that the second electron donor is a pterin cofactor, H4B. However, several questions concerning electron transfer in the NO-producing step (NOHA oxidation) remains to be addressed: the number of electron transfer (one vs two), the nature of the oxidative