Cyclopropane fatty acids constitute 25% of the phospholipid acyl groups in cysts of Azotobacter vinelandii. These are lost by dilution during germination when the synthesis of the fatty acids characteristic of vegetative cell phospholipids commences.

azotobacter vinelandii, a gamma-proteobacterium, is an obligate aerobic free-living gram-negative soil bacterium capable of fixing nitrogen. oxygen transfer rate into the cell is reduced by the increase of alginate concentrations during the course of a. vinelandii cultivation. this phenomenon provides a low intracellular oxygen concentration needed for nitrogenase activity. the aim of this stud...

The gene encoding the noncoupled NADH:ubiquinone oxidoreductase (NDH II) from Azotobacter vinelandii was cloned, sequenced, and used to construct an NDH II-deficient mutant strain. Compared to the wild type, this strain showed a marked decrease in respiratory activity. It was unable to grow diazotrophically at high aeration, while it was fully capable of growth at low aeration or in the presenc...

Azotobacter vinelandii contains a heterodimeric, membrane-bound [NiFelhydrogenase capable of catalyzing the reversible oxidation of H2. The 13 and at subunits of the enzyme are encoded by the structural genes hoxK and hoxG, respectively, which appear to form part of an operon that contains at least one further potential gene (open reading frame 3 1ORF3]). In this study, determination of the nuc...

The 19.9 kDa C-terminal module (R3) from Azotobacter vinelandii mannronan C5-epimerase AlgE6 has been (13)C, (15)N isotopically labelled and recombinantly expressed. We report here the (1)H, (13)C, (15)N resonance assignment of AlgE6R3.

Quantitative N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) oxidase and superoxide dismutase (SOD) analyses were performed on representative organisms of the family Azotobacteraceae. Azotobacter vinelandii, Azotobacter chroococcum, Azotobacter paspali, and Derxia gummosa exhibited high quantitative TMPD oxidase activities, and their extracts possessed very active and electrophoretically homoge...

Vegetative cells and cysts of Azotobacter vinelandii 12837 were prepared for electron microscopy by several methods assumed to preserve structural details destroyed by techniques previously reported in the literature. Examination of large numbers of cells and cysts by these methods revealed four structural details not reported previously: intine fibrils, intine vesicles, intine membrane, and mi...