Open AccessKinetics of Coupled Reactions Catalyzed by Aspartate Aminotransferase and Glutamate Dehydrogenase
Author(s) -
SALERNO Costantino,
OVÁDI Judit,
KELETI Tamás,
FASELLA Paolo
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb05816.x
Subject(s) - glutamate dehydrogenase , transaminase , enzyme , catalysis , chemistry , dehydrogenase , kinetics , phase (matter) , lactate dehydrogenase , biochemistry , glutamate receptor , stereochemistry , organic chemistry , physics , receptor , quantum mechanics
Liver mitochondrial aspartate aminotransferase and glutamate dehydrogenase catalyze the following sequence of reactions:In the presence of a slight excess of dehydrogenase, the time course of NADPH oxidation resulting from the overall reaction goes through a lag phase and reaches a linear phase. The slope of the linear part of this curve is a linear function of transaminase concentration. At high concentration (∼ 10 μM) of both enzymes the lag phase, as observed after rapid mixing of the two enzymes in a Durrum stopped‐flow spectrophotometer, is shorter than that predicted from the kinetic parameters determined for the separate reactions catalyzed by each enzyme