| Autor: |
Streicher SL, Shanmugam KT, Ausubel F, Morandi C, Goldberg RB |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of bacteriology [J Bacteriol] 1974 Nov; Vol. 120 (2), pp. 815-21. |
| DOI: |
10.1128/jb.120.2.815-821.1974 |
| Abstrakt: |
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(-) phenotype, continue to synthesize nitrogenase in the presence of NH(4) (+). One strain, KP5069, produces 30% as much nitrogenase when grown in the presence of 15 mM NH(4) (+) as in its absence. The GlnC(-) phenotype allows the synthesis of nitrogenase to continue under conditions that completely repress nitrogenase synthesis in the wild-type strain. Glutamine auxotrophs of K. pneumoniae, that do not produce catalytically active glutamine synthetase, are unable to synthesize nitrogenase during nitrogen limited growth. Complementation of K. pneumoniae Gln(-) strains by an Escherichia coli episome (F'133) simultaneously restores glutamine synthetase activity and the ability to synthesize nitrogenase. These results indicate a role for glutamine synthetase as a positive control element for nitrogen fixation in K. pneumoniae. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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