Nitrate reductase activity in spheroplasts from Rhodobacter capsulatus E1F1 requires a periplasmic protein

1993 ◽  
Vol 160 (6) ◽  
pp. 471-476 ◽  
Author(s):  
Maria M. Dobao ◽  
Manuel Mart�nez-Luque ◽  
Francisco Castillo
Keyword(s):  
Nitrate Reductase ◽  
Nitrate Reductase Activity ◽  
Rhodobacter Capsulatus ◽  
Reductase Activity ◽  
Periplasmic Protein

Effect of carbon and nitrogen metabolism on nitrate reductase activity of Rhodobacter capsulatus E1F1

1994 ◽  
Vol 40 (8) ◽  
pp. 645-650 ◽  
Author(s):  
María M. Dobao ◽  
Manuel Martínez-Luque ◽  
Conrado Moreno-Vivián ◽  
Francisco Castillo
Keyword(s):  
Nitrate Reductase ◽  
Nitrogen Metabolism ◽  
Nitrogen Balance ◽  
Nitrate Reductase Activity ◽  
Rhodobacter Capsulatus ◽  
Reductase Activity ◽  
Intracellular Concentration ◽  
Carbon And Nitrogen ◽  
Nitrate Concentrations ◽  
Carbon And Nitrogen Metabolism

The phototrophic bacterium Rhodobacter capsulatus E1F1 possesses an assimilatory, inducible nitrate reductase that is regulated by carbon and nitrogen metabolism. Nitrate reductase activity was detected in cells cultured with amino acids and nitrate as simultaneous nitrogen source but it required an additional carbon source such as D,L-malate. A significant rise in nitrate reductase activity was observed in media with increasing nitrate concentrations up to 10 mM KNO3, although higher nitrate concentrations had an inhibitory effect. Growth yield, generation time, and nitrate reductase activity were also dependent on the concentration of D,L-malate in cells growing with 10 mM nitrate. In carbon-starved cells, nitrate reductase activity dropped even in the presence of nitrate. The intracellular concentration of keto acids such as oxaloacetate or 2-oxoglutarate fluctuated widely depending on the presence of nitrogen and carbon sources in the culture medium. The increase in the intracellular concentration of oxaloacetate or 2-oxoglutarate in R. capsulatus E1F1 correlated well with a rise in nitrate reductase activity. These results suggest that the intracellular carbon–nitrogen balance regulates nitrate uptake in R. capsulatus E1F1, thus affecting the expression of nitrate reductase.Key words: carbon–nitrogen balance, nitrate reductase, Rhodobacter capsulatus.

No Correlation between Plasmid Content and Ability to Reduce Nitrate in Wild-Type Strains of Rhodobacter capsulatus

1991 ◽  
Vol 46 (7-8) ◽  
pp. 703-705 ◽  
Author(s):  
Astrid Witt ◽  
Jobst-Heinrich Klemme
Keyword(s):  
Nitrate Reductase ◽  
Nitrate Reductase Activity ◽  
Rhodobacter Capsulatus ◽  
Reductase Activity ◽  
Large Plasmid ◽  
Wild Type ◽  
Plasmid Content ◽  
Phototrophic Bacterium ◽  
N Source ◽  
Type Strains

Patterns of endogenous plasmids and nitrate reductase activities were analyzed in the phototrophic bacterium Rhodobacter (Rb.) capsulatus. From 10 strains investigated (including a UV-induced plasmidless nit- mutant), 4 were unable to grow photosynthetically with nitrate as N-source and lacked nitrate reductase activity (nit strains). Irrespective of the nit phenotype, all wildtype strains contained at least one large plasmid with a size ranging from 93 to 134 kb. Thus, other than in plasmid- cured mutants (J. C. Willison, FEMS Microbiol. Lett. 66, 23-28[1990]), in wild-type strains of Rb. capsulatus the nit- character was not related to lack of endogenous plasmids.

Nitrate Reductase Activity of Maize Hybrids and Their Parental Inbred 1

Crop Science ◽  
1966 ◽  
Vol 6 (2) ◽  
pp. 169-173 ◽  
Author(s):  
L. E. Schrader ◽  
D. M. Peterson ◽  
E. R. Leng ◽  
R. H. Hageman
Keyword(s):  
Nitrate Reductase ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Maize Hybrids ◽  
Parental Inbred

Chromosomal Control of Nitrate Reductase Activity in Hexaploid Wheat 1

Crop Science ◽  
1982 ◽  
Vol 22 (1) ◽  
pp. 85-88 ◽  
Author(s):  
E. L. Deckard ◽  
N. D. Williams ◽  
J. J. Hammond ◽  
L. R. Joppa
Keyword(s):  
Nitrate Reductase ◽  
Hexaploid Wheat ◽  
Nitrate Reductase Activity ◽  
Reductase Activity

scholarly journals Antagonism of chloride and nitrate inhibits nitrate reductase activity in chloride-stressed maize

2021 ◽  
Author(s):  
Xudong Zhang ◽  
Bastian L. Franzisky ◽  
Lars Eigner ◽  
Christoph‐Martin Geilfus ◽  
Christian Zörb
Keyword(s):  
Zea Mays ◽  
Polyethylene Glycol ◽  
Nitrate Reductase ◽  
Osmotic Stress ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Shoot Biomass ◽  
Lower Intensity ◽  
Maize Variety ◽  
Osmotic Balance

AbstractChloride (Cl−) is required for photosynthesis and regulates osmotic balance. However, excess Cl− application negatively interacts with nitrate ($${\mathrm{NO}}_{3}^{-}$$ NO 3 - ) uptake, although its effect on $${\mathrm{NO}}_{3}^{-}$$ NO 3 - metabolism remains unclear. The aim was to test whether Cl− stress disturbs nitrate reductase activity (NRA). A maize variety (Zea mays L. cv. LG 30215) was hydroponically cultured in a greenhouse under the following conditions: control (2 mM CaCl2), moderate Cl− (10 mM CaCl2), high Cl− (60 mM CaCl2). To substantiate the effect of Cl− stress further, an osmotic stress with lower intensity was induced by 60 g polyethylene glycol (PEG) 6000 L−1 + 2 mM CaCl2), which was 57% of the osmotic pressure being produced by 60 mM CaCl2. Results show that high Cl− and PEG-induced osmotic stress significantly reduced shoot biomass, stomatal conductance and transpiration rate, but NRA was only decreased by high Cl− stress. The interference of NRA in chloride-stressed maize is supposed to be primarily caused by the antagonistic uptake of Cl− and $${\mathrm{NO}}_{3}^{-}$$ NO 3 - .

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