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Glutamate Synthase: Properties oftheReduced Nicotinamide Adenine Dinucleotide-Dependent Enzymefrom Saccharomyces cerevisiae
Fred Larimore
- 01 Jan 1974
84
TL;DR: Variations in the specific activity of glutamate synthase, which occur in response to changes in the growth medium, are similar in character to those observed with the nicotinamide adenine dinucleotide phosphate-dependent (anabolic) glutamate dehydrogenase.
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Abstract: A reduced nicotinamide adenine dinucleotide (NADH)-dependent glutamate synthase hasbeendetected andpartially purified fromcrudeextracts of Saccharomyces cerevisiae. Theenzyme isspecific forNADH, glutamine, and a-ketoglutarate (Kmvalues of2.6,uM,1.0mM, and140AM,respectively) and hasa pHoptimumbetween 7.1and7.7.Thestoichiometry ofthereaction has beendetermined as 2 molofglutamate synthesized per molofglutamine consumed. Glutamate synthase can bedistinguished fromeither oftheglutamatedehydrogenases ofyeaston thebasis ofitssubstrate requirements and behavior during agarosegelandionexchange chromatography. Variations inthe specific activity ofglutamate synthase, which occur inresponse tochanges inthe growth medium, aresimilar incharacter tothose observed withthenicotinamide adenine dinucleotide phosphate-dependent (anabolic) glutamate dehydrogenase.
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Citations
The Enzymes of Ammonia Assimilation in Schizosaccharomyces spp. and in Saccharomycodes ludwigii
B. Johnson,C. M. Brown +1 more
TL;DR: The results of chemostat studies on the levels of enzymes involved in ammonia assimilation in representatives of the four recognizedspecies of the genus Schizosaccharomyces and the single recognized species of the related genus Saccharomy codes are reported.
22
Regulation by ammonium of glutamate dehydrogenase (NADP+) from Saccharomyces cerevisiae.
TL;DR: The following results suggest that the decrease in NADP-GDH activity in ammonia-accumulating yeast cells is brought about by repression of synthesis.
Ammonia Assimilation by Aspergillus nidulans: [15N]Ammonia Study
TL;DR: Observations with these two inhibitors suggest that ammonia assimilation can occur concurrently via the glutamine synthetase/glutamate synthase and the glutamate dehydrogenase pathways in low-ammonia-grown A. nidulans.
21
Glutamine Degradation Through the ω-Amidase Pathway in Saccharomyces cerevisiae
Mario Soberón,Alicia Gonzaález +1 more
TL;DR: A glutamine transaminase activity has been identified in Saccharomyces cerevisiae, and the existence of the ω-amidase activity previously described in this yeast has been confirmed.
21
Cloning, sequencing and expression of the Schwanniomyces occidentalis NADP-dependent glutamate dehydrogenase gene.
TL;DR: The cloned NADP-specific glutamate dehydrogenase (GDH) genes of Aspergillus nidulans and Neurospora crassa have been shown to hybridize under reduced stringency conditions to genomic sequences of the yeast Schwanniomyces occidentalis.
21
References
‘Glutamine(amide): 2-Oxoglutarate Amino Transferase Oxido-reductase (NADP)’, an Enzyme Involved in the Synthesis of Glutamate by Some Bacteria
TL;DR: Ammonia-limited Aerobacter aerogenes, Erwinia carotovora, Pseudomonas fluorescens, Bacillus subtilis and B. megaterium synthesized glutamate from NH3 and 2-oxoglutarate by a process that involved first the synthesis of glutamine and then the reductive transfer of the glutamine amide-nitrogen to the 2-position of 2-OxoglUTarate.
Glutamate synthase from Escherichia coli. An iron-sulfide flavoprotein.
TL;DR: Glutamate synthase catalyzes the TPNH-dependent conversion of α-ketoglutarate and l-glutamine to glutamate, which results in significantly lower levels of enzyme produced when glutamate replaces NH4Cl as the source of nitrogen.
278
Release of the “ammonia effect” on three catabolic enzymes by NADP-specific glutamate dehydrogenaseless mutations in Saccharomyces cerevisiae
TL;DR: In this paper, two mechanisms of action of these mutations have to be considered, namely a modification of the process of induction (such as removal of inducer exclusion) and a suppression of nitrogen catabolite repression.
74
Synthesis of glutamate by a glutamine: 2-oxo-glutarate amidotransferase (NADP oxidoreductase) in Bacillus megaterium.
TL;DR: The properties of GGAT and the physiological study of mutants deficient in GGAT or GlnS activity suggest that these coupled reactions represent the major if not the only pathway of glutamate synthesis.
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