Control of photosystem genes in Rhodobacter capsulatus.
Two environmental factors, oxygen and high light intensity, are known to repress synthesis of the Rhodobacter capsulatus photosystem. One level of regulation is the control of light harvesting and reaction centre gene expression at the point of transcription initiation. This has recently been shown to involve transcriptional activators which exhibit sequence similarity to members of the 'two-component' class of prokaryotic regulators. An additional level of regulation involves the formation of 'superoperons' that transcriptionally link pigment biosynthesis operons with operons that code for the light harvesting and reaction centre structural genes. A final level of regulation involves the selective degradation of reaction centre mRNA transcripts which influence the stoichiometric synthesis of the light harvesting and reaction centre complexes.
Bauer
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Department of Biology, Indiana University, Bloomington 47405.
Buggy
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Mosley
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D000693:Anaerobiosis; D001429:Bacteriochlorophylls / Q000096:biosynthesis / Q000235:genetics; D001483:Base Sequence; D002338:Carotenoids / Q000096:biosynthesis; D016384:Consensus Sequence; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008027:Light; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D009876:Operon; D010788:Photosynthesis / Q000235:genetics*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics* / Q000528:radiation effects; D011401:Promoter Regions, Genetic; D012323:RNA Processing, Post-Transcriptional; D016354:Rhodobacter capsulatus / Q000235:genetics* / Q000502:physiology / Q000528:radiation effects; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D001429:Bacteriochlorophylls; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D002338:Carotenoids