Membrane potential, proton and sodium motive forces in Azospirillum brasilense Sp7-S
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Membrane potential, proton and sodium motive forces in Azospirillum brasilense Sp7-S
Some biophysical features of the diazotroph Azospirillum brasilense Sp7-S were studied. It maintained a stable but relatively low membrane potential (v8) of about 385 mV in conditions typical of aerated soil solutions. Internal pH was also well regulated at about 7.4 from pH 6^8. The calculated proton motive force was maximal at 3220 mV in pH 5.0 medium, decreasing to zero at pH 8.8. This proto...
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Spectral analysis indicated the presence of a cytochrome cbb3 oxidase under microaerobic conditions in Azospirillum brasilense Sp7 cells. The corresponding genes (cytNOQP) were isolated by using PCR. These genes are organized in an operon, preceded by a putative anaerobox. The phenotype of an A. brasilense cytN mutant was analyzed. Under aerobic conditions, the specific growth rate during expon...
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ژورنال
عنوان ژورنال: FEMS Microbiology Letters
سال: 1998
ISSN: 0378-1097
DOI: 10.1016/s0378-1097(98)00230-4