An ArsR/SmtB family member is involved in the regulation by arsenic of the arsenite oxidase operon in Thiomonas arsenitoxydans.

ABSTRACT: The genetic organization of the aioBA operon, encoding the arsenite oxidase of the moderately acidophilic and facultative chemoautotrophic bacterium Thiomonas arsenitoxydans, is different from that of the aioBA operon in the other arsenite oxidizers, in that it encodes AioF, a metalloprotein belonging to the ArsR/SmtB family. AioF is stabilized by arsenite, arsenate, or antimonite but not molybdate. Arsenic is tightly attached to AioF, likely by cysteine residues. When loaded with arsenite or arsenate, AioF is able to bind specifically to the regulatory region of the aio operon at two distinct positions. In Thiomonas arsenitoxydans, the promoters of aioX and aioB are convergent, suggesting that transcriptional interference occurs. These results indicate that the regulation of the aioBA ope

SUBMITTER: Moinier D 

PROVIDER: S-EPMC4178639 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature