Glutamine synthetase, glutamate synthase and glutamate dehydrogenase in Rhizobium japonicum strains grown in cultures and in bacteroids from root nodules of Glycine max

Planta ◽  
1983 ◽  
Vol 159 (3) ◽  
pp. 207-215 ◽  
Author(s):  
Franklin Vairinhos ◽  
Basant Bhandari ◽  
D. J. D. Nicholas
Keyword(s):  
Glycine Max ◽  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Root Nodules ◽  
Glutamate Synthase ◽  
Rhizobium Japonicum

Ammonia, glutamine, and asparagine: a carbon–nitrogen interface

1988 ◽  
Vol 66 (10) ◽  
pp. 2103-2109 ◽  
Author(s):  
K. W. Joy
Keyword(s):  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Higher Plants ◽  
Amino Nitrogen ◽  
Glutamate Synthase ◽  
Dinitrogen Fixation ◽  
Similar Function ◽  
Metabolic Processes ◽  
Organic Form ◽  
Primary Input

In plants, the primary input of nitrogen (obtained from the soil or from symbiotic dinitrogen fixation) occurs through the assimilation of ammonia into organic form. Synthesis of glutamine (via glutamine synthetase) is the major, and possibly exclusive, route for this process, and there is little evidence for the participation of glutamate dehydrogenase. A variety of reactions distribute glutamine nitrogen to other compounds, including transfer to amino nitrogen through glutamate synthase. In many plants asparagine is a major recipient of glutamine nitrogen and provides a mobile reservoir for transport to sites of growth; ureides perform a similar function in some legumes. Utilisation of transport forms of nitrogen, and a number of other metabolic processes, involves release of ammonia, which must be reassimilated. In illuminated leaves, there is an extensive flux of ammonia released by the photorespiratory cycle, requiring continuous efficient reassimilation. Aspects of ammonia recycling and related amide metabolism in higher plants are reviewed.

Occurrence of ferredoxin-dependent glutamate synthase in plant cell fraction of soybean root nodules (Glycine max )

FEBS Letters ◽  
1984 ◽  
Vol 173 (1) ◽  
pp. 204-208 ◽  
Author(s):  
Akira Suzuki ◽  
Jean Vidal ◽  
Jacqueline Nguyen ◽  
Pierre Gadal
Keyword(s):  
Glycine Max ◽  
Plant Cell ◽  
Root Nodules ◽  
Glutamate Synthase ◽  
Cell Fraction ◽  
Soybean Root

scholarly journals Distinctive properties and expression profiles of glutamine synthetase from a plant symbiotic fungus

2003 ◽  
Vol 373 (2) ◽  
pp. 357-368 ◽  
Author(s):  
Barbara MONTANINI ◽  
Marco BETTI ◽  
Antonio J. MÁRQUEZ ◽  
Raffaella BALESTRINI ◽  
Paola BONFANTE ◽  
...  
Keyword(s):  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Expression Profiles ◽  
Glutamate Synthase ◽  
Synthetase Activity ◽  
Mrna Levels ◽  
Glutamine Synthetase Activity ◽  
Tuber Borchii ◽  
Root Cells ◽  
N Assimilation

Nitrogen retrieval and assimilation by symbiotic ectomycorrhizal fungi is thought to play a central role in the mutualistic interaction between these organisms and their plant hosts. Here we report on the molecular characterization of the key N-assimilation enzyme glutamine synthetase from the mycorrhizal ascomycete Tuber borchii (TbGS). TbGS displayed a strong positive co-operativity (n=1.7±0.29) and an unusually high S0.5 value (54±16 mM; S0.5 is the substrate concentration value at which v=½Vmax) for glutamate, and a correspondingly low sensitivity towards inhibition by the glutamate analogue herbicide phosphinothricin. The TbGS mRNA, which is encoded by a single-copy gene in the Tuber genome, was up-regulated in N-starved mycelia and returned to basal levels upon resupplementation of various forms of N, the most effective of which was nitrate. Both responses were accompanied by parallel variations of TbGS protein amount and glutamine synthetase activity, thus indicating that TbGS levels are primarily controlled at the pre-translational level. As revealed by a comparative analysis of the TbGS mRNA and of the mRNAs for the metabolically related enzymes glutamate dehydrogenase and glutamate synthase, TbGS is not only the sole messenger that positively responds to N starvation, but also the most abundant under N-limiting conditions. A similar, but even more discriminating expression pattern, with practically undetectable glutamate dehydrogenase mRNA levels, was observed in fruitbodies. The TbGS mRNA was also found to be expressed in symbiosis-engaged hyphae, with distinctively higher hybridization signals in hyphae that were penetrating among and within root cells.

scholarly journals Some Properties of Glutamine Synthetase From the Nitrifying Bacterium Nitrosomonas Euro Paea

1981 ◽  
Vol 34 (6) ◽  
pp. 527 ◽  
Author(s):  
Basant Bhandari ◽  
DJD Nicholas
Keyword(s):  
Glutamine Synthetase ◽  
Glutamic Acid ◽  
Glutamate Dehydrogenase ◽  
Glutamate Synthase ◽  
Nitrosomonas Europaea ◽  
Main Route

Nitrosomonas europaea oxidizes ammonia to nitrite, thereby deriving energy for growth. Glutamate dehydrogenase (NADP+) (EC 1.4.1.4) is the main route for the incorporation of ammonia into glutamic acid, because glutamate synthase (NADPH) (EC 1.4.1.13) was not detected in cell-free extracts of N. europaea.

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