The genome sequence of Azotobacter vinelandii: an obligate aerobic pseudomonad specialized to support diverse anaerobic metabolic processes

SETUBAL JC; DOS SANTOS P; GOLDMAN B; ERTESVÅG H; ESPIN G; RUBIO LM; VALLA S; ALMEIDA NF; BALASUBRAMANIAN D; CROMES L; CURATTI L; DU Z; GODSY E; GOODNER B; HELLNER-BURRIS K; HERNANDEZ JA; HOUMIEL K; IMPERIAL J; KENNEDY C; LARSON TJ; LATREILLE P; LIGON LE; LU J; MÆRK M; MILLER MN; NORTON S; OCARROLL IP; PAULSEN I; RAULFS E; ROEMER R; ROSSER J; SEGURA D; SLATER S; STRICKLIN SL; STUDHOLME DJ; SUN J; VIANA CJ; WALLIN E; WANG B; WHEELER BW; ZHU H; DEAN DR; DIXON R; WOOD D

Villa Carlos Paz

Workshop; II Argentine Workshop of Pseudomonas and Burkholderia; 2009

La Sociedad de Biología de Córdoba

Azotobacter vinelandii is a soil bacterium related to the Pseudomonas genus that displays a remarkable capacity for aerobic nitrogen fixation. Here we report the complete genome sequence of A. vinelandii strain DJ. Whole genome phylogenetic analysis confirms that A. vinelandii groups with other pseudomonads (family Pseudomonadaceae). Among the pseudomonads, the closest relative is P. stutzeri A1501, a nitrogen-fixing strain. A. vinelandii and P. stutzeri A1501 share about 44% and 54% of their respective protein-coding genes. Whole chromosome alignment between A. vinelandii DJ and P. stutzeri A1501 shows large scale conservation of gene order, however, many rearrangements have also taken place since these two species diverged.In order to reconcile an obligate aerobic lifestyle with exquisitely oxygen-sensitive processes, A.vinelandii is specialized in terms of its complement of respiratory proteins and has multiple duplications of alginate modification genes that help to further protect the organism from excess exogenous oxygen. The genome analysis not only showed the chromosomal location of the three known oxygen-sensitive nitrogenases and its hydrogenase, but also identified previously unknown putative genes for other oxygen-sensitive enzymes, such as carbon monoxide dehydrogenase, formate dehydrogenase and a soluble second [Ni-Fe]-hydrogenase system. These findings offer new prospects for the study of A. vinelandii physiology and highlight the convenience of the use of this strain as a host for the production and biochemical characterization of oxygen-sensitive proteins. Curatti´s work at CEBB is supported by CONICET and ANPCyT