title: Pigments accumulation via light and oxygen in Rhodobacter capsulatus strain XJ-1 isolated from saline soil.
abstract: A Rhodobacter capsulatus strain, designated XJ-1, isolated from saline soil, accumulated almost only one kind of bacteriochlorophyll a anaerobically in the light, aerobically in the light and dark, and the relative contents of the bacteriochlorophyll a were 44.61, 74.89, and 77.53% of the total pigments, respectively. A new purple pigment appeared only in aerobic-light grown cells, exhibited absorption maxima at 355, 389, 520, 621, and 755 nm, especially distinctly unusual peak at 621 nm, whereas vanished in anaerobic-light and in aerobic-dark culture. Spheroidene and OH-spheroidene predominated in anaerobic phototrophic cultures. Spheroidenone was the sole carotenoid when exposed to both light and oxygen. The second keto-carotenoids, OH-spheroidenone, presented only in aerobic-dark culture in addition to spheroidenone. Strain XJ-1 would be a good model organism for the further illustration of the regulation of bacteriochlorophyll biosynthesis gene expression in response to unique habitat.
authors.affiliation: College of Life Science, Shanxi University, Taiyuan, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Lin
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Cui
authors.forename: Chungui
authors.initials: C
authors.lastname: Zhao
authors.forename: Suping
authors.initials: S
authors.lastname: Yang
authors.forename: Johannes F
authors.initials: JF
authors.lastname: Imhoff
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D001429:Bacteriochlorophylls / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D002338:Carotenoids / Q000378:metabolism; D008027:Light; D013058:Mass Spectrometry; D010100:Oxygen; D010674:Pheophytins / Q000378:metabolism*; D016354:Rhodobacter capsulatus / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D054712:Salinity; D012965:Sodium Chloride / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology
chemical_list: D001426:Bacterial Proteins; D001429:Bacteriochlorophylls; D010674:Pheophytins; D012987:Soil; C026083:bacteriochlorophyll A proteins, Bacteria; C005637:spheroidene; C104880:spheroidenone; C006678:bacteriopheophytin; D002338:Carotenoids; D012965:Sodium Chloride; D010100:Oxygen
keywords: Bacteriochlorophyll; Oxygen and light; Purple pigment; Rhodobacter capsulatus; Saline soil