The Bradyrhizobium japonicum exporter ExsFGH is involved in efflux of ferric xenosiderophores from the periplasm.

ABSTRACT: The gram-negative bacterium Bradyrhizobium japonicum can take up structurally dissimilar ferric siderophores from the environment (xenosiderophores) to meet its nutritional iron requirements. Siderophore-bound iron transported into the periplasm is reduced to the ferrous form by FsrB, dissociated from the siderophore and the free ion is then transported into the cytoplasm by the ferrous iron transporter FeoAB. Here, we identified the RND family exporter genes exsFG and exsH in a selection for secondary site suppressor mutants that restore growth of an fsrB mutant on the siderophores ferrichrome or ferrioxamine. The low level of radiolabel accumulation from 55Fe-labeled ferrichrome or ferrioxamine observed in the fsrB mutant was restored to wild type levels in the fsrB exsG mutant. Moreover

SUBMITTER: Ong A 

PROVIDER: S-EPMC10760861 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature