Citrate inhibition of rat-kidney cortex phosphofructokinase.
The regulatory properties of citrate on the activity of phosphofructokinase (PFK) purified from rat-kidney cortex has been studied. Citrate produces increases in the K0.5 for Fru-6-P and in the Hill coefficient as well as a decrease in the Vmax of the reaction without affecting the kinetic parameters for ATP as substrate. ATP potentiates synergistically the effects of citrate as an inhibitor of the enzyme. Fru-2,6-P2 and AMP at concentrations equal to Ka were not able to completely prevent citrate inhibition of the enzyme. Physiological concentrations of ATP and citrate produce a strong inhibition of renal PFK suggesting that may participate in the control of glycolysis in vivo.
Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Granada, Spain.
M M
MM
Sola
F J
FJ
Oliver
R
R
Salto
M
M
Gutiérrez
A
A
Vargas
D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D002951:Citrates / Q000494:pharmacology*; D019343:Citric Acid; D005636:Fructosephosphates / Q000032:analysis; D007672:Kidney Cortex / Q000187:drug effects* / Q000201:enzymology; D007700:Kinetics; D008297:Male; D010732:Phosphofructokinase-1 / Q000037:antagonists & inhibitors*; D051381:Rats; D017208:Rats, Wistar
D002951:Citrates; D005636:Fructosephosphates; D019343:Citric Acid; C027618:fructose-6-phosphate; D000255:Adenosine Triphosphate; D010732:Phosphofructokinase-1