title: Pigment analysis of "Candidatus Chlorothrix halophila," a green filamentous anoxygenic phototrophic bacterium.
abstract: The pigment composition of "Candidatus Chlorothrix halophila," a filamentous anoxygenic phototrophic bacterium found in Baja California Sur, Mexico, was determined. Previous work showed that bacteriochlorophyll c (BChl c) was the major pigment in "Ca. Chlorothrix halophila," but it was not clear if this bacterium also contains BChl a (J. A. Klappenbach and B. K. Pierson, Arch. Microbiol. 181:17-25, 2004). Here we show that in addition to BChl c, a small amount of a pigment that is spectrally indistinguishable from BChl a is present in cell extracts of "Ca. Chlorothrix halophila." Nevertheless, the BChl a-like pigment from "Ca. Chlorothrix halophila" has a different molecular weight and a different high-performance liquid chromatography elution time than BChl a from other photosynthetic bacteria. Based on mass spectrometry and other spectroscopic analysis, we determined that the BChl a-like pigment in "Ca. Chlorothrix halophila" contains a tetrahydrogeranylgeraniol tail rather than the phytol tail that is present in BChl a. The carotenoids and major BChl c homologs in "Ca. Chlorothrix halophila" were also identified. BChls c were found to be farnesol esterified and geranylgeraniol esterified.
authors: Department of Biology and Chemistry, Arizona State University, Tempe, AZ 85287, USA.
authors: Tien Le
authors: TL
authors: Olson
authors: Allison M L
authors: AM
authors: van de Meene
authors: J Nicholas
authors: JN
authors: Francis
authors: Beverly K
authors: BK
authors: Pierson
authors: Robert E
authors: RE
authors: Blankenship
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D025541:Bacteriochlorophyll A / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D001429:Bacteriochlorophylls / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D002338:Carotenoids / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D041862:Chloroflexi / Q000378:metabolism* / Q000648:ultrastructure; D002851:Chromatography, High Pressure Liquid; D046529:Microscopy, Electron, Transmission; D015394:Molecular Structure; D010860:Pigments, Biological / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001426:Bacterial Proteins; D025541:Bacteriochlorophyll A; D001429:Bacteriochlorophylls; D010860:Pigments, Biological; D002338:Carotenoids; C002084:bacteriochlorophyll c