Regulation of photosynthesis genes in Rubrivivax gelatinosus: transcription factor PpsR is involved in both negative and positive control.

ABSTRACT: Induction of biosynthesis of the photosystem in anoxygenic photosynthetic bacteria occurs when the oxygen concentration drops. Control of this induction takes place primarily at the transcriptional level, with photosynthesis genes expressed preferentially under anaerobic conditions. Here, we report analysis of the transcriptional control of two photosynthesis promoters, pucBA and crtI, by the PpsR factor in Rubrivivax gelatinosus. This was accomplished by analyzing the photosystem production in the wild type and in the PPSRK (ppsR::Km) mutant grown under anaerobic and semiaerobic conditions and by assessing the beta-galactosidase activity of lacZ transcriptionally fused to promoters possessing the putative PpsR-binding consensus sequences. It was found that under semiaerobic conditions, in

SUBMITTER: Steunou AS 

PROVIDER: S-EPMC400625 | biostudies-literature | 2004 May

REPOSITORIES: biostudies-literature