Substrate antagonism in the kinetic mechanism of E. coli phosphofructokinase‐1

FEBS Letters

Deville-Bonne, Dominique¹  Laine, Romuald¹  Garel, Jean-Renaud¹ 

[1] Laboratoire d'Ezymologie du CNRS, 91198 Gif-sur-Yvette, France

关键词: Escherichia coli;    Phosphofructokinase;    Enzyme mechanism;    Binding interaction;    Fru-6P;    D-fructose-6-phosphate;    Ara-5P;    D-arabinose-5-phosphate;    Fru-1;    6P2;    D-fructose-1;    6-bisphosphate;    AMPPCP;    adenylyl-(β;    γ-methylene)-diphosphonate;    PKF;    phosphofructokinase (ATP-D-fructose-6-phosphate I-phosphotransferase;    EC 2.7.1.11);   

DOI  :  10.1016/0014-5793(91)81253-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In the presence of its allosteric activator GDP, the major phosphofructokinase-1 from Escherichia coli K12 follows Michaelis—Menten kinetics. The kinetic behavior observed at steady-state using different concentrations of the substrates ATP and fructose-6-phosphate and the pattern of inhibition by the substrate analogs adenylyl-(β,γ-methylene)-diphosphonate and D-arabinose-5-phosphate are consistent with a random sequential mechanism in rapid equilibrium, rather than with an ordered binding as was suggested earlier. However, ATP and fructose-6-phosphate do not bind independently to the same active site, since the apparent affinity for one substrate is decreased about 20-fold when the other substrate is already bound. The antagonism between ATP and fructose-6-phosphate shows that a negative interaction occurs during the reaction with E. coli phosphofructokinase-1 which must be considered in addition to its allosteric properties.

【 授权许可】

Unknown