Sinorhizobium meliloti bluB is necessary for production of 5,6-dimethylbenzimidazole, the lower ligand of B12.

ABSTRACT: An insight into a previously unknown step in B(12) biosynthesis was unexpectedly obtained through our analysis of a mutant of the symbiotic nitrogen fixing bacterium Sinorhizobium meliloti. This mutant was identified based on its unusually bright fluorescence on plates containing the succinoglycan binding dye calcofluor. The mutant contains a Tn5 insertion in a gene that has not been characterized previously in S. meliloti. The closest known homolog is the bluB gene of Rhodobacter capsulatus, which is implicated in the biosynthesis of B(12) (cobalamin). The S. meliloti bluB mutant is unable to grow in minimal media and fails to establish a symbiosis with alfalfa, and these defects can be rescued by the addition of vitamin B(12) (cyanocobalamin) or the lower ligand of cobalamin, 5,6-dimethy

SUBMITTER: Campbell GR 

PROVIDER: S-EPMC1450223 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature