Results 151 to 160 of about 9,744 (190)

Inhibition of nitrogenase activity by metronidazole in Rhodopseudomonas capsulata

Archives of Microbiology, 1981
Inhibition of photosynthetic growth of Rhodopseudomonas capsulata by metronidazole was dependent on the nitrogen supply in culture solutions. Cultures fixing dinitrogen were more susceptible to inhibition by low concentrations than those supplied with NH4+.
B C, Kelley, D J, Nicholas
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Regulation and Control of Nitrogenase Activity

1983
The acquisition of reduced nitrogen is the port of entry for protein synthesis, nucleotide and coenzyme metabolism and other nitrogen-requiring metabolites. Diazotrophically-growing organisms spend a considerable amount of energy to use dinitrogen for this process and, thus, have it embedded in a subtly tuned, regulatory system. Since the capability of
Daniel J. Arp, Walter G. Zumft
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Purification and Mn2+ activation of Rhodospirillum rubrum nitrogenase activating enzyme

Journal of Bacteriology, 1982
The Fe protein activating enzyme for Rhodospirillum rubrum nitrogenase was purified to approximately 90% homogeneity, using DE52-cellulose chromatography and sucrose density gradient centrifugation. Activating enzyme consists of a single polypeptide of molecular weight approximately 24,000.
J W, Gotto, D C, Yoch
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Nitrogenase activity in root nodule homogenates of Alnus incana

Plant and Soil, 1984
Root nodule homogenates of actinorhizal plants may represent Frankia in a symbiotic stage but released from environmental influence of the host plant. Anaerobic homogenization with a blender in buffer supplied with sucrose, polyvinylpyrrolidone and reducing substances gave three times higher yields of nitrogenase activity (C2H2-reduction) than crushing
Kerstin Huss-Danell, Ann-Sofi Ahlqvist
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Sodium is required for nitrogenase activity in cyanobacteria

Current Microbiology, 1980
The cyanobacteriaAnabaena torulosa andAnabaena L-31 require sodium (Na+) for growth on N2 but not in the presence of NH4 +. Na+-starved cultures show relatively little or no nitrogenase activity although they differentiate normal heterocysts. Nitrogenase activity appears rapidly on addition of Na+ to Na+-starved cultures.
S. K. Apte, Joseph Thomas
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Regulation of Nitrogenase Activity by Reversible ADP Ribosylation

1989
Publisher Summary This chapter discusses the molecular bases for Gest and Kamen's observations and attempts to put these observations into perspective with respect to the regulation of the nitrogenase enzyme complex by the reversible ADP ribosylation of dinitrogenase reductase.
P W, Ludden, G P, Roberts
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A Theoretical Model for the Active Site of Nitrogenase

Chemistry – A European Journal, 1996
AbstractA model for the active site of nitrogenase is suggested and examined by means of the intermediate neglect of differential overlap (INDO) quantum mechanical method. The initial steps of the nitrogen fixation process are discussed within the framework of the present model, and it is shown that of several binding sites, initial location of the ...
Krassimir K. Stavrev, Michael C. Zerner
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A model of nitrogenase active-centre and mechanism of nitrogenase catalysis.

Scientia Sinica, 1977
Based upon the known reactions of nitrogenase and the principles of coordination catalysis, a model of nitrogenase active-centre is proposed. An octa-atomic cluster, Fe2S2-Mo2O2, of pseudo-cubane-type structure is supposed to form a coupled twin of trinuclear (2Mo-1Fe) active-centre, which also catalyzes the reduction of H+ to H2.
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Multimetallic Models of the Nitrogenase Active Site

2021
Motivated by the lack of an atomic-level understanding of the reduction of small molecule substrates by nitrogenase, this dissertation describes the synthesis, characterization and reactivity of well-defined model clusters of the enzyme active site.
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Chemical Modification of the Active Center of Nitrogenase

1992
The MoFe-protein of nitrogenase consists of two atom clusters (Kurtz et al. 1979, Mortenson et al. 1979). The first is the atom cluster of Fe4S4, four of which are contained in each MoFe-protein (Mw 22 kDa). The second is FeMo—co (Shah et al. 1978), two of which are contained in each MoFe-protein; it consists of one Mo, seven to eight Fe and six S2 ...
X. P. Dai, J. S. Yang, C. G. Zhang
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