title: Genes involved in the biosynthesis of photosynthetic pigments in the purple sulfur photosynthetic bacterium Thiocapsa roseopersicina.
abstract: A pigment mutant strain of the purple sulfur photosynthetic bacterium Thiocapsa roseopersicina BBS was isolated by plasposon mutagenesis. Nineteen open reading frame, most of which are thought to be genes involved in the biosynthesis of carotenoids, bacteriochlorophyll, and the photosynthetic reaction center, were identified surrounding the plasposon in a 22-kb-long chromosomal locus. The general arrangement of the photosynthetic genes was similar to that in other purple photosynthetic bacteria; however, the locations of a few genes occurring in this region were unusual. Most of the gene products showed the highest similarity to the corresponding proteins in Rubrivivax gelatinosus. The plasposon was inserted into the crtD gene, likely inactivating crtC as well, and the carotenoid composition of the mutant strain corresponded to the aborted spirilloxanthin pathway. Homologous and heterologous complementation experiments indicated a conserved function of CrtC and CrtD in the purple photosynthetic bacteria. The crtDC and crtE genes were shown to be regulated by oxygen, and a role of CrtJ in aerobic repression was suggested.
authors.affiliation: Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary.
authors.forename: Akos T
authors.initials: AT
authors.lastname: Kovács
authors.forename: Gábor
authors.initials: G
authors.lastname: Rákhely
authors.forename: Kornél L
authors.initials: KL
authors.lastname: Kovács
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001429:Bacteriochlorophylls / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D002338:Carotenoids / Q000096:biosynthesis* / Q000235:genetics; D004251:DNA Transposable Elements; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D005810:Multigene Family; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames / Q000235:genetics; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D020616:Thiocapsa roseopersicina / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D001429:Bacteriochlorophylls; D004251:DNA Transposable Elements; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D002338:Carotenoids