Regulated expression of a highly conserved regulatory gene cluster is necessary for controlling photosynthesis gene expression in response to anaerobiosis in Rhodobacter capsulatus

Primer extension analysis was employed to show that the divergently transcribed regB and senC-regA-hvrA transcripts contain stable 5' ends 43 nucleotides apart within the regB-senC intergenic region in Rhodobacter capsulatus. Findings indicated that autoregulation by RegA is a factor contributing to the maintenance of an optimal low level of RegA expression that permits responsiveness to activation by phosphorylation.