title: Distribution of colored carotenoids between light-harvesting complexes in the process of recovering carotenoid biosynthesis in Ectothiorhodospira haloalkaliphila cells.
abstract: The processes of recovering colored-carotenoid (Car) biosynthesis in Car-less cells of the purple sulfur bacterium Ectothiorhodospira haloalkaliphila grown with diphenylamine (DPA-cells) have been studied. It has been found that (1) the rate of recovering colored-Car biosynthesis in the lag-phase is far ahead of the growth rate of the cells themselves; (2) several Cars (ζ-carotene, neurosporene etc.) act as intermediates in Car biosynthesis; (3) because filling the "empty" Car pockets in the LH1-RC complexes is faster than in LH2, available spirilloxanthin is preferentially incorporated into the nascent LH1-RC core particles; (4) as a consequence of the resulting lack of spirilloxanthin availability, the biosynthetic intermediates (anhydrorhodovibrin, rhodopin and lycopene) fill the empty nascent LH2 Car pockets. In the present report, we further discuss the process of colored Car incorporation into LH complexes during the recovery of Car biosynthesis in the DPA-cells of Ect.haloalkaliphila.
authors.affiliation: Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Ashikhmin
authors.affiliation: Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
authors.forename: Zoya
authors.initials: Z
authors.lastname: Makhneva
authors.affiliation: Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
authors.forename: Maksim
authors.initials: M
authors.lastname: Bolshakov
authors.affiliation: Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia. Electronic address: andrey-moskalenko@rambler.ru.
authors.forename: Andrey
authors.initials: A
authors.lastname: Moskalenko
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis* / Q000737:chemistry; D004159:Diphenylamine / Q000737:chemistry / Q000378:metabolism; D020587:Ectothiorhodospira / Q000254:growth & development / Q000378:metabolism*; D045342:Light-Harvesting Protein Complexes / Q000378:metabolism*; D013053:Spectrophotometry; D024341:Xanthophylls / Q000096:biosynthesis / Q000737:chemistry
chemical_list: D045342:Light-Harvesting Protein Complexes; D024341:Xanthophylls; D002338:Carotenoids; C008604:neurosporene; D004159:Diphenylamine; C055255:spirilloxanthin
keywords: Carotenogenesis; Carotenoids; Diphenylamine; Ectothiorhodospira haloalkaliphila; Photosynthesis; “empty” Carotenoid pocket