Glutamate dehydrogenase substrate

Figure 29-5. The i-glutamate dehydrogenase reaction. NAD(P) means that either NAD or NADP can serve as co-substrate. The reaction is reversible but favors glutamate formation.

Very low concentrations of substrates may be assayed by recycling the test substrate for an appreciable but definite period of time and measuring the amount of product formed. The coenzyme NADPH, for instance, may be assayed using the two enzymes glutamate dehydrogenase (EC 1.4.1.3) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) ... 

It is a substrate for the formation of glutamate from oxoglutarate in a reaction catalysed by the enzyme glutamate dehydrogenase. 

A three-substrate, three-product enzyme reaction scheme in which all substrates bind and all products are released in an ordered sequence. Glutamate dehydrogenase at a pH 8.8 has been reported to have this reaction scheme. 

A three-substrate, three-product enzyme-catalyzed reaction scheme in which the three substrates (A, B, and C) and three products (P, Q, and R) can bind to and be released in any order. A number of enzymes have been reported to have this mechanism for example, adenylosuccinate synthetase , glutamate dehydrogenase, glutamine synthetase , formyltetrahydrofolate synthetase, and tubulin tyrosine ligase . See Multisubstrate Mechanisms... 

See specific aminotransferase Glutamate as a substrate or product, GLUTAMATE DECARBOXYLASE GLUTAMATE DEHYDROGENASE GLUTAMATE SYNTHASE GLUTAMINE SYNTHETASE y-GLUTAMYL TRANSPEPTIDASE LEUCINE AMINOTRANSEERASE LYSINE 6-AMINOTRANSEERASE... 

P. C. Engel, and D. W. Rice, Insights into the mechanism of domain closure and substrate sof glutamate dehydrogenase from Clostridium symbosium, J. Mol. Biol. 1999, 285, 875-885. 

Enzymes that catalyze redox reactions often require a coenzyme such as NAD+ or FADH2 in addition to a substrate. These are all multiple substrate enzymes. Each substrate and coenzyme will have its own Km value. The substrates for glutamate dehydrogenase, an enzyme with three substrates in both forward and reverse directions, are shown in Scheme 4.10 with their K values.9... 

Pressure activation and inactivation is investigated for several enzymes like penicillin amidase (E.coli), glutamate dehydrogenase (P. woesei) and lipase (Rhizopus arrhizus) in the pressure range between 1 bar and 4000 bar. In dependance of pressure and temperature the enzymes are acivated or inactivated and hence their enantioselectiviy can be directed. The activation of the enzymes corresponds to a decrease in the KM value which results in a higher substrate affinity. ... 

For glyceraldehyde-3-phosphate dehydrogenase, glutamate dehydrogenase, and the NADP-linked oxidative decarboxylases, which have three substrates in one direction, initial rate measurements with a fixed concentration of any one of the three substrates also conform to Eq. (1). This again rules out any form of enzyme-substitution mechanism in which free product is formed before all the substrates have combined with the enzyme and indicates the involvement of a quaternary enzyme complex. The appropriate generalized form of Eq. (1) is... 

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