Genus Specific Unusual Carotenoids in Purple Bacteria, Phaeospirillum and Roseospira: Structures and Biosyntheses

Department of Biology, Nippon Medical School, 297, Kosugi-cho 2, Nakahara, Kawasaki, 211-0063, Japan.
Current Microbiology (Impact Factor: 1.42). 07/2011; 63(1):75-80. DOI: 10.1007/s00284-011-9941-1
Source: PubMed


Phototrophic bacteria necessarily contain carotenoids for photosynthesis, and a few phototrophic purple bacteria accumulate unusual carotenoids. The carotenoids in the genera Phaeospirillum and Roseospira were identified using spectroscopic methods. All species of the genus Phaeospirillum contained characteristic polar carotenoids in addition to lycopene and hydroxylycopene (rhodopin); hydroxylycopene glucoside, dihydroxylycopene, and its mono- and/or diglucosides. From the structures of these carotenoids, their accumulation was suggested to be due to absence of CrtD (acyclic carotenoid C-3,4 desaturase) and to possession of glucosyltransferase. Species of the genus Roseospira have been reported to have unusual absorption spectra in acetone extract, and they were found to accumulate 3,4-didehydrorhodopin as a major carotenoid. This may be due to low activity of CrtF (acyclic 1-hydroxycarotenoid methyltransferase). The study concludes in identifying genus specific unusual carotenoids, which is probably due to characteristic nature of some carotenogenesis enzymes.

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Available from: Shinichi Takaichi, Jan 21, 2015
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    • "Data revealed that the novel isolates clustered with type strains of species of the genus Phaeospirillum and were distinct from other genera of purple non-sulfur bacteria. The genotypic association of the novel isolates to the genus Phaeospirillum is also supported by the presence of carotenoid glycosides, an important chemotaxonomic character which distinguishes these members from other genera of the family Rhodospirillaceae (Lakshmi et al., 2011a; Takaichi et al., 2011). The highest sequence similarities for both the isolates were found with P "
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