Regulation of the phototrophic iron oxidation (pio) genes in Rhodopseudomonas palustris TIE-1 is mediated by the global regulator, FixK.

ABSTRACT: The pioABC operon is required for phototrophic iron oxidative (photoferrotrophic) growth by the α-proteobacterium Rhodopseudomonas palustris TIE-1. Expression analysis of this operon showed that it was transcribed and translated during anaerobic growth, upregulation being observed only under photoferrotrophic conditions. Very low levels of transcription were observed during aerobic growth, suggesting expression was induced by anoxia. The presence of two canonical FixK boxes upstream of the identified pioABC transcription start site implicated FixK as a likely regulator. To test this possibility, a ΔfixK mutant of R. palustris TIE-1 was assessed for pioABC expression. pioABC expression decreased dramatically in ΔfixK versus WT during photoferrotrophic growth, implying that FixK positively r

SUBMITTER: Bose A 

PROVIDER: S-EPMC3050613 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature