Characterization of the DraT/DraG system for posttranslational regulation of nitrogenase in the endophytic betaproteobacterium Azoarcus sp. strain BH72.

ABSTRACT: DraT/DraG-mediated posttranslational regulation of the nitrogenase Fe protein by ADP-ribosylation has been described for a few diazotrophic bacteria belonging to the class Alphaproteobacteria. Here we present for the first time the DraT/DraG system of a betaproteobacterium, Azoarcus sp. strain BH72, a diazotrophic grass endophyte. Its genome harbors one draT ortholog and two physically unlinked genes coding for ADP-ribosylhydrolases. Northern blot analysis revealed cotranscription of draT with two genes encoding hypothetical proteins. Furthermore, draT and draG2 were expressed under all studied conditions, whereas draG1 expression was nitrogen regulated. By using Western blot analysis of deletion mutants and nitrogenase assays in vivo, we demonstrated that DraT is required for the nitrogen

SUBMITTER: Oetjen J 

PROVIDER: S-EPMC2681912 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature