BIOCHEMICAL
Vol. 12, No. 2, 1963
EED-PRODUCT IEHIBI!J!ION
AND BIOPHYSICAL
RESEARCH COMMUNICATIONS
OF YEAST PHOSPHOFRUCICOKIRASE BY AU? '
E. Vi5uela,2
Maria IL S~&W,~
and A. Sol8
Department of Enzymology, Instituto MarafXdn, Centro de Investigaoionea Bioldgicas, C.S.I.C., Madrid, Spain
Received
May
20,
1963
Some relation reaction twenty
to the Pasteur years,
colysis
effect
even after
became centered
acceptor. ed for
of the phosphofructokinase
Indirect
and for
yeast
has been suspected
on the phosphate for
(Iynea
et al.,
Maitra
and Steinberg,
1963),
1959),
and muscle (Park et al.,
1961).
Direct
and its
counteraction
ly reported
for
and Mansour,
for
lity
Fasciola
it
ascites
Research
(Negelein,
by A!l!P competitively
not supported
by
Newsholme and Randle, has been recent1962).
Nothing
was
where the Pasteur
1936),
In addition
there
was a possibi-
than the muscle enzyme.
below show that with
of the Comissria
1957)
and muscle PFK (Mansour
could be less unstable
Fellow
has been claim-
of PFK by excess ATP
hepatioa
found.
of glg-
tumor (Lonberg-Holm,
1961;
This work was supported by a research Public Health Service (RC-8041). 2
over
phosphate
and Potter,
1959; although
inhibition
The data presented inhibited
relation
Passonneau and Lowry,
1962;
was originally that
and/or
by severalmetabolites
known on the PFK of yeast effect
this
systems (Aisenberg
evidence
for
the emphasis on the control
evidence
reconstructed
(PFK)
yeast PFK is
fructose-6-phosphate grant
from U.S.
de Proteocicn
Escolar.
BIOCHEMICAL
Vol. 12, No. 2, 1963
(FSP),
in such a way that
logical with
AND BIOPHYSICAL
concentrations the increase
the square
the normal rauge
the activity
of F6P concentration.
end-product
It
and increases is suggested
as the end product
irreversible
with
that ATP
of the pathway whose
step is the PFK reaction,
inhibition
of physio-
of the enzyme decreases
of ATP concentration
may be considered first
within
RESEARCH COMMUNICATIONS
and that
by ATP can act as a feed-back
oontrol
in glycolyaia.
The effect PFK activity Fig.
3 at a given
1. If
Within
plot
kinetics.
respect
3
is no inhibition
the same range. of F6P corresponds
lines
with respeot lines
with
(B). The reaction
if
ATP is substituted the double
respect
by GTP (Fig. plots
reciprocal
to the concentration to the square
becomes first
reciprocal
the
to second
2, the double
to F6P at very high F6P/ATP ratios
conditions, (Fig.
by GTP, there
As shown in Pig.
and straight
of the latter
of F6P is shown in
a wide range of UP concentrations,
gave parabolic
of F6P (A),
ranges
within
of the concentration
order
of &l!P on yeast
concentration
ATP is substituted
by excess nucleotide effect
of the concentration
order
with
and over wider 3A). Under these
give
parallel
lines
3).
Yeast PFK was obtained by extracting dried brewers yeast (Anheuser and Busch, "for enzyme work") with 6 volumes of 0.1 M KHCO3 - 1 mltl CH -CH2SH - 1 mM EDTA. The fraction precipitated between i 0 and 60 per cent saturation of (NE4)2SO4 was dialyzed against several changes of 0.05 Y potassium phosphate - 5 mM MgC12 - 1 m&I CH3-CH2SH - 1 ti EDTA, pH 7.5. This PFK preparation is free of ATPase and is stable within the assay conditions in this work. 141
Vol. 12, No. 2, 1963
BIOCHEMICAL
AND BlOPHYSlCAi.
RESEARCH COMMUNICATIONS
t3TP Oo3 d 2 t z 3
/-
0.2 /p \\
O-l !
NP 1 Q6
I 1
I 1.5
.I 2
(XTP) llw
Fig.
1. Yeast phoaphofructokinaae activity GTP, at 0.9 mM fructose&-P.
with ATP and
PFK activity wae assayed by following the decrease in optrcal density at 340 mfl in the presence of excess aldolase, trioae phosphate ieomerase, and LO(-glycerophosphate dehydrogenaae (Boehringer), 0.1 mM DPKH, 0.05 M Tris pH 7.5, 5 m&l CH3-CH#H, 10 mM MgC12, P6P (obtained by treating glucose&-P with glucose phoaphate isomeraae and assuming the concentration of F6P in the equilibrated mixture to be l/4 of the total ester), and ATP or GTP a8 indicated in the figures. The reaction was started by the addition of the PFK preparation. Kate is expressed a8 )unolea of Hub&rate tranaformed per min per mg protein.
I
2
3
WFbPh
4
5
sol5m25
lo-’
fl/F6Pho-.
Fig, 2. Effect of the concentration of fructose-6-P phoephofructokinaee activity at the concentrations ATP-Mg indicated in the figure, in millimolea/l. Other assay conditione as in Fig. 1.
No appreciable (at inhibitory -3',5'-AMP,
levels
effect
on the activity
of ATP) was observed
AMP, ADP, or FDP (using
of yeast PFK
with Pi,
in the latter
on of
cyoliccase the
Vol. t2, No. 2, 1963
pyruvate range
BIOCHEMICAL
kinase-lactic
dehydrogenase
of concentrations
I
AND BIOPHYSICAL
RESEARCH COMMUNICATIONS
method)
within
the
used by Passonneau and Dowry (1962).
I
I
1
2
I 3
I 4
(l/F6P)xlo-3
WGTP)xlo-’
Pig. 3. KXnetice of the phosphofructokinase reaction in non-inhibitory conditions. Assay conditions as in Pig. 1, at the concentrations of GTP and F6P indicated in the figure.
DISCTJSSIOB The strong
inhibition
of yeast PFK by excess ATP,
but not by excess GTP (see Fig. has a regulatory
binding
site
for
substrate
site.
occupancy
of the regulatory
occupancy
of the sugar substrate
order
kinetics
Competition
l),
suggests ATP different
with F6P further
with respect
site
panty
that
for
ATP, or simply
of a bridging
site.
suggests
Moreover,
site
involve
ATP regulatory
those of F6P in two active
with
respect 1963).
from the that
with the second
to F6P which accompany inhibition
with Sols,
the enzyme
by ATP interferes
could depend on a second regulatory with
that
for
F6P interfering
a dimer in which oocusite
sites.
could
be competitive
Second order
kinetics
to F6P is shown also by muscle PPK (Vifiuela The second order
kinetics 143
in relation
and
to some
BIOCHEMICAL
Vol. 12, No. 2, 1963
regulatory
inhibitions
(Chsngeux,
may have a general
1962)
AND BIOPHYSICAL
in terms of polymerized
lation,
possibly
that
simultaneously
Similar
kinetics
on a given
llhia Its
pathway after
irreversible
site
with
over a wide range and $018,
(Moyed and Umbarger, in this tive
with
case the end product
enzyme. !l!he fact
ing A!CP within trations
that
leads to A!l!P production. Inhibition
in normal
biosynthetic
pathways
the additional
novelty
PFK activity
decreases
range
yeast suggests
that
this control
In aerobiosis,
Such a feed-back
the rate
of the A!l!P-producing
all
of net disposal
rate
mediates
(for
glycolytic
of A!I!P, without
an illustration
see Holzer, 144
of the sensiwith
increas-
end-product mechanism
the increased
of A!L'P per mole of hexosemonophosphate
brake the PFK reaction.
that
of ATP and F6P concen-
by A!CP can act as a feed-back yeast glycolysis.
inhibition
is also a substrate
the physiological
in fermenting
inhibition yield
1962),
of the cross-road.
step is the PFK reaction.
for
of
1963).
as the end product
specifically
established
1953).
a muscle PFK prepa-
of PFK by A!l?P would then be a case of end-product in the sense well
condi-
(Alberty,
the hexosemonophoaphate
is the pathway that first
active
(VifXuela
ATP may be considered glycolytic
levels, F6P and A!l?P, are not
to A!l?P inhibition,
ATP and F6P concentrations
regu-
of the
of yeast PFK in non-inhibition
have been observed
desensitized
as mechanism,
sensititity
the two substrates,
present
and Pardee,
enzymes. For metabolic
enzyme to changes in metabolite
suggests
ration
far
As
in terms of increased
The kinetics tions
Gerhart
1961;
significance.
perhaps regulable
RESEARCH COMMUNICATIONS
would further
control
could adjust
pathway to the overpiling 1961).
up of inter-
BIOCHEMICAL
Vol. 12, No. 2, 1963
AND BIOPHYSICAL
Passonneau and Lowry (1962) large
increase
in PFK activity
when the ATP concentration ficance
is the fact
competitive
with
that
have emphasized
the
in muscle that may be expected
falls,
Of possible
the inhibition
greater
signi-
of PFKa by ATP is
the square of the F6P concentration.
property
opens a way for
activity
by the large
in stimulated
RESEARCH COMMUNICATIONS
automatic,
increase
muscle,
before
drastic
forcing
in F6P formation any marked fall
This of PFK
that
occurs
in the ATP
level. Further lation
work on the mechaniwne
of metabolic
regu-
of yeast and muscle PFKs ia in progress,
Aisenberg,
B.C.,
and Potter,
V.R.,
J. Biol.
Chem., 224,
1115 (1957).
Alberty, R.A., J. Am. Chem. Sot., 75, 1928 (1953). Chameux, J., Cold Spring Harbor S.ymp. on Quant. Biol., - 3,
3i3
(i961).
26,
277 (1961).
-
-
;erh.ert, J-C., and Pardee, A.B., J. Biol. Chem., 237, Ztn+ f*nfz.?\ Cold Spring Herbor Symp. on Quant. Biol., Holzer,‘H,, Lon'Fj;Eirg-Holm, ILK., Biochim. Biophys. Acta, 35, 464 (1959). Lynen, E., Hartmann, G., Wetter, K.F., and Schuegraf, A., in G.E.W. Wolstehholme and C.M. O'Connor (Editors) Regulation of Cell Metabolism, J. & A. Churchill, London, 1959, p. 256. Maitra, P.K., and-Steinberg, S.E., Federation Proc., 22, 240 (1963).
Mansour,
T.E., and Manaour, J.M., J. Biol. Chem., a, ( 1962). Yoyed, H.S., and Umberger, H.E.,Physiol. Revs., $2, 444 629
(1962).
Regelein, E., Biochem. Z., 287, 329 (1936). Rewsholme, E.A., and RandleT.J., Biochem.J., 80, 655 (1961). Park, C.R., Morgan, H.E., Henderson, Y.J., Regen, D.M., Cadenas, E., and Post, R.L., Recent Progr. Horm. Rea., IJ, 493 (1961). Passonneau, J.V., and Lowry, O.H., Biochem. Biophys. Res. commull., 2, 10 (1962). Vifiuela, E., and Sols, A., in preparation (1963). 145