Correlation of ultrastructure in Azotobacter vinelandii with nitrogen source for growth.

Correlation between nitrogen fixation rate and alginate productivity of an indigenous Azotobacter vinelandii from Iran

BACKGROUND AND OBJECTIVES 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 acti...

Evaluation of three methods for preservation of Azotobacter chroococcum and Azotobacter vinelandii

Plant growth-promoting bacteria –PGPB– are microorganisms that can grow in, on, or around plant tissues and stimulate plant growth by numerous mechanisms (Vessey 2003). Within this group, nitrogen-fixing bacteria play a remarkable role in plant nutritition. They can take N2 from atmosphere and make it available for plant uptake (Halbleib and Ludden 2000). Azotobacter, a nitrogen-fixing bacteria...

Hydroxylamine as a Source of Nitrogen for Azotobacter Vinelandii.

Control of transformation competence in Azotobacter vinelandii by nitrogen catabolite derepression.

Azotobacter vinelandii (ATCC 12837) became competent to be transformed by exogenous deoxyribonucleic acid towards the end of exponential growth. Competence in wild-type and nitrogenase auxotrophic (nif-) strains was repressed by the addition of ammonium salts or urea to the transformation medium. Transformation of wild-type cells and nif- strains was optimal on nitrogen-free or nitrogen-limitin...

Cyst formation and poly-beta-hydroxybutyric acid accumulation in Azotobacter.

Stevenson, L. H. (Louisiana State University, Baton Rouge), and M. D. Socolofsky. Cyst formation and poly-beta-hydroxybutyric acid accumulation in Azotobacter. J. Bacteriol. 91:304-310. 1966.-The relationship between cyst formation and the accumulation of poly-beta-hydroxybutyric acid (PHB) in Azotobacter vinelandii (A. agilis) was investigated. After various periods of growth, the cells were h...