Analysis Note
Protein determined by biuret
Unit Definition
One unit will reduce 1.0 μmole of α-ketoglutarate to L-glutamate per min at pH 7.3 at 25 °C, in the presence of ammonium ions.
Physical form
Suspension in 2.0 M (NH4)2SO4 solution, pH 7.0
Biochem/physiol Actions
Mammalian forms of this enzyme, including this bovine form, can use either NADP(H) or NAD(H) as coenzymes. L-glutamic dehydrogenase plays a unique role in mammalian metabolism. The reverse reaction catalyzed by this enzyme is the only pathway by which ammonia can become bound to the α-carbon atom of an α-carboxylic acid and thus, is the only source of de novo amino acid synthesis in mammalian species.
The bovine enzyme is characterized by three sets of properties:
It has a reversible concentration-dependent association, producing higher molecular weight forms.
Forms tight enzyme-reduced coenzyme-substrate ternary complexes whose rates of dissociation modulate the steady-state reaction rates.
Exhibits a wide variety of effects from the binding of any of a number of nucleotide modifiers.