A double enzyme of Salmonella typhimuriwn, containing histidinol dehydrogenase and imidazolylacetolphosphate:~glutamate aminotransferase, was mildly proteolyzed in an attempt to release these activities from covalent linkage. This treatment releases an active histidinol dehydrogenase fragment larger than normal histidinol dehydrogenase, while completely destroying aminotransferase activity. The...

l-Glutamate uptake, thiourea uptake, and methylammonium uptake and the intracellular ammonium concentration were measured in wild-type and mutant cells of Aspergillus nidulans held in various concentrations of ammonium and urea. The levels of l-glutamate uptake, thiourea uptake, nitrate reductase, and hypoxanthine dehydrogenase activity are determined by the extracellular ammonium concentration...

The influence of the synthetic phenylurea cytokinin 4-PU-30 and of the adenin cytokinin kinetin on the chilling and freezing stress of tobacco callus was studied histochemically. The investigations were carried out immediately after the low-temperature stress and after 20 days cultivation. It was established that alcohol dehydrogenase and glutamate dehydrogenase activities decreased but esteras...

Germinating spores of Geotrichum candidum produce only a nicotinamide adenine dinucleotide phosphate-linked glutamate dehydrogenase. Synthesis of glutamate dehydrogenase was repressed by the presence of ammonia, whereas urea, glutamate, or glutamine were ineffective. The enzyme was not subject to catabolite repression and was localized in the cell sap fraction. The glutamate dehydrogenase has b...

The nicotinamide adenine dinucleotide-specific glutamate dehydrogenase (l-glutamate:NAD(+) oxidoreductase, EC 1.4.1.2) of Chlorella sorokiniana was purified 1,000-fold to electrophoretic homogeneity. The native enzyme was shown to have a molecular weight of 180,000 and to be composed of four identical subunits with a molecular weight of 45,000. The N-terminal amino acid was determined to be lys...

Amino acid dehydrogenases (AADHs) are a group of enzymes that catalyze the reversible reductive amination keto acids with ammonia to produce chiral amino using either nicotinamide adenine dinucleotide (NAD+) or phosphate (NADP+) as cofactors. Among them, glutamate dehydrogenase, valine leucine phenylalanine and tryptophan dehydrogenase have been classified superfamily (s-AADHs) by previous rese...