Investigation on the Kinetic Mechanism of Octopine Dehydrogenase. A Regulatory Behavior

Abstract

The kinetic scheme of octopine dehydrogenase of Pecten maximus L., a monomeric enzyme obeying a bi-ter sequential mechanism, was completed, essentially in the forward reaction, by steady-state studies over a wide range of substrate concentration at pH 7.0. Deviation from the Michaelis-Menten behavior with respect to NAD⁺ and other significant kinetic data led us to ascribe for octopine dehydrogenase mechanism the mnemonical enzyme concept. In addition, another regulatory behavior can be envisaged involving the formation of two dead-end complexes enzyme·NADH·d-octopine and enzyme·NAD⁺·pyruvate·l-arginine.