Differing isoforms of the cobalamin binding photoreceptor AerR oppositely regulate photosystem expression.

ABSTRACT: Phototrophic microorganisms adjust photosystem synthesis in response to changes in light intensity and wavelength. A variety of different photoreceptors regulate this process. Purple photosynthetic bacteria synthesize a novel photoreceptor AerR that uses cobalamin (B₁₂) as a blue-light absorbing chromophore to control photosystem synthesis. AerR directly interacts with the redox responding transcription factor CrtJ, affecting CrtJ's interaction with photosystem promoters. In this study, we show that AerR is translated as two isoforms that differ by 41 amino acids at the amino terminus. The ratio of these isoforms was affected by light and cell growth phase with the long variant predominating during photosynthetic exponential growth and the short variant predominating in dark con

SUBMITTER: Yamamoto H 

PROVIDER: S-EPMC6199135 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature