Rhodopseudomonas palustris, Glutamine Synthetase, Dye-Ligand Chromatography, Nitrogen Fixation, Ammonium Assimilation The phototrophic bacterium Rhodopseudomonas palustris assimilated ammonium via glutamine synthetase and glutamate synthase. Diazotrophic and ammonium-grown cells had high levels of both enzymes, whereas enzymes of alternative assimilatory pathways were absent or had only low act...

Saccharomyces cerevisiae glutaminyl-tRNA synthetase mutants were isolated through systematic screening of tight Glnderivatives of a leaky glutamine auxotroph. These mutations define a single nuclear gene, GLN4. The gln4-1 mutation is specific for Gln-tRNA synthetase and shows a dosage effect in heterozygous diploids. The wild-type Gln-tRNA synthetase exhibits a Km for glutamine of 25 ,uM; the g...

The book is well produced by photo-offset reproduction from typescript and contains a large number of figures, illustrations and diagrams. There is a comprehensive collection of references which is complete until 1972. The work is divided into two parts, the first dealing with enzymes involved in glutamats-glutamine interconversion and the second discussing those enzymes that use the amide nitr...

The first step in the proteolytic degradation of bacterial glutamine synthetase is a mixed function oxidation of one of the 16 histidine residues in the glutamine synthetase subunit (Levine, R. L. (1983) J. Biol. Chem. 258, 11823-11827). A model system, consisting of oxygen, a metal ion, and ascorbic acid, mimics the bacterial system in mediating the oxidative modification of glutamine syntheta...

Under certain conditions of growth, the Escherichiu coli glutamine synthetase is modified by the introduction into the enzyme molecule of covalently bound adenylic acid. This mechanism for modification of the preformed enzyme was discovered independently in this country by Kingdon and Stadtman (1, 2) and in Germany by Holzer et al. (3, 4). An enzyme was described by Kingdon, Shapiro, and Stadtm...

Mutations causing constitutive synthesis of glutamine synthetase (GlnC(-) phenotype) were transferred from Klebsiella aerogenes into Klebsiella pneumoniae by P1-mediated transduction. Such GlnC(-) strains of K. pneumoniae have constitutive levels of glutamine synthetase. Two of three GlnC(-) strains of K. pneumoniae studied, each containing independently isolated mutations that confer the GlnC(...

The cortisol induction of the enzyme glutamine synthetase (EC 6.4.1.2) in the embryonic chick neural retina is controlled initially at the transcriptional level, as previously demonstrated by the unique appearance of a 15 S RNA species which codes for a single and identical polypeptide chain of glutamine synthetase. This is found only on polyribosomes of cortisol-treated retinas. Recent experim...

The cortisol induction of the enzyme glutamine synthetase (EC 6.4.1.2) in the embryonic chick neural retina is controlled initially at the transcriptional level, as previously demonstrated by the unique appearance of a 15 S RNA species which codes for a single and identical polypeptide chain of glutamine synthetase. This is found only on polyribosomes of cortisol-treated retinas. Recent experim...

Glutamine synthetase was localized in nodules, roots, stems, and leaves of red kidney bean (Phaseolus vulgaris L.) by immunocytochemistry. Affinity purified antibodies reactive with glutamine synthetase were prepared using purified nodule-enhanced glutamine synthetase. Immunogold labeling was observed in the cell cytoplasm in each plant organ. In nodules, the labeling was more intense in the in...

Bacillus subtilis TnrA, a global regulator of transcription, responds to nitrogen availability, but the specific signal to which it responds has been elusive. Genetic studies indicate that glutamine synthetase is required for the regulation of TnrA activity in vivo. We report here that the feedback-inhibited form of glutamine synthetase directly interacts with TnrA and blocks the DNA binding ac...