The present study was aimed to evaluate the therapeutic potential of Pimpinella tirupatiensis (Pt) by assaying the activities of selective mitochondrial enzymes in streptozotocin induced diabetic rats. Diabetic rats showed a significant (p < 0.01) reduction in the activities of oxidative enzymes Succinate dehydrogenase (SDH), Malate dehydrogenase (MDH), Glutamate dehydrogenase (GDH) and isocitr...

The relationship between oxidized nicotinamide adenine dinucleotide (phosphate) [NAD(P)+] transhydrogenase (EC 1.6.1.1) and NAD(P)+ glutamate dehydrogenase in several enteric bacteria which differ slightly in their regulation of nitrogen metabolism was studied. Escherichia coli strain K-12 was grown on glucose and various concentrations of NH4Cl as the sole nitrogen source. In the range of 0.5 ...

In previous studies it was found that: (a) aspartate aminotransferase increases the aspartate dehydrogenase activity of glutamate dehydrogenase; (b) the pyridoxamine-P form of this aminotransferase can form an enzyme-enzyme complex with glutamate dehydrogenase; and (c) the pyridoxamine-P form can be dehydrogenated to the pyridoxal-P form by glutamate dehydrogenase. It was therefore concluded (F...

Mutants of Salmonella typhimurium defective in glutamate dehydrogenase activity were isolated in parent strains lacking glutamate synthase activity by localizcd mutagenesis or by a general mutagenesis combined with a cycloserine enrichment for glutamate auxotrophs. Two mutants with temperature-sensitive phenotypes had glutamate dehydrogenase activities that were more thermolabile than that of a...

The regulation of glutamate dehydrogenase (EC 1.4.1.4), glutamine synthetase (EC 6.3.1.2), and glutamate synthase (EC 2.6.1.53) was examined for cultures of Salmonella typhimurium grown with various nitrogen and amino acid sources. In contrast to the regulatory pattern observed in Klebsiella aerogenes, the glutamate dehydrogenase levels of S. typhimurium do not decrease when glutamine synthetas...

When wild-type cells of Aspergilbrs nidulans were grown on -N medium (minimal medium minus a N source) with ammonia, glutamate, aspartate or alanine as sole N sources there was low L-glutamate-NAD oxidoreductase (EC 1.4.1.2) activity. A similar result was obtained when cells were grown as before and then deprived of N for periods of up to 6h. However, it was found that when cells were transferr...

We have also examined similar parameters for several other enzymes; the trend suggests that in these cases there is a correlation between apparent association constant and capacity. These enzymes include yeast glutathione reductase, glucose 6-phosphate dehydrogenase, glutamate dehydrogenase, alcohol dehydrogenase and malate dehydrogenase, Neurospora crassa glutamate dehydrogenase, pig heart iso...

Flooding induces low-oxygen stress, which reduces plant growth. The activity of the γ-aminobutyric acid (GABA) shunt is crucial for stress adaptation, in it acts by changing cytosolic pH, limiting reactive oxygen species production, regulating nitrogen metabolism, and bypassing steps tricarboxylic cycle. GABA accumulates under osmotic as well flooding stress. To clarify dynamic roles accumulati...

The present study was aimed to evaluate the therapeutic potential of Pimpinella tirupatiensis (Pt) by assaying the activities of selective mitochondrial enzymes in streptozotocin induced diabetic rats. Diabetic rats showed a significant (p < 0.01) reduction in the activities of oxidative enzymes Succinate dehydrogenase (SDH), Malate dehydrogenase (MDH), Glutamate dehydrogenase (GDH) and isocitr...

We have found previously (Fahien, L.A., Kmiotek, E.H., MacDonald, M. J., Fibich, B., and Mandic, M. (1988) J. Biol. Chem. 263, 10687-10697) that glutamate-malate oxidation can be enhanced by cooperative binding of mitochondrial aspartate aminotransferase and malate dehydrogenase to the alpha-ketoglutarate dehydrogenase complex. The present results demonstrate that glutamate dehydrogenase, which...