title: Phosphatidylglycerol depletion induces an increase in myxoxanthophyll biosynthetic activity in Synechocystis PCC6803 cells.
abstract: Phosphatidylglycerol (PG) depletion suppressed the oxygen-evolving activity of Synechocystis PCC6803 pgsA mutant cells. Shortage of PG led to decreased photosynthetic activity, which, similar to the effect of high light exposure, is likely to generate the production of reactive oxygen species (ROS) or free radicals. Protection of the PG-depleted cells against light-induced damage increased the echinenone and myxoxanthophyll content of the cells. The increased carotenoid content was localized in a soluble fraction of the cells as well as in isolated thylakoid and cytoplasmic membranes. The soluble carotenoid fraction contained carotene derivatives, which may bind to proteins. These carotene-protein complexes are similar to orange carotenoid protein that is involved in yielding protection against free radicals and ROS. An increase in the content of myxoxanthophyll and echinenone upon PG depletion suggests that PG depletion regulates the biosynthetic pathway of specific carotenoids.
authors.affiliation: Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Ildiko
authors.initials: I
authors.lastname: Domonkos
authors.forename: Przemyslaw
authors.initials: P
authors.lastname: Malec
authors.forename: Hajnalka
authors.initials: H
authors.lastname: Laczko-Dobos
authors.forename: Ozge
authors.initials: O
authors.lastname: Sozer
authors.forename: Kinga
authors.initials: K
authors.lastname: Klodawska
authors.forename: Hajime
authors.initials: H
authors.lastname: Wada
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Strzalka
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Gombos
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis; D008027:Light; D009154:Mutation; D010715:Phosphatidylglycerols / Q000378:metabolism*; D010788:Photosynthesis; D046939:Synechocystis / Q000235:genetics / Q000378:metabolism*; D020524:Thylakoids / Q000378:metabolism; D024341:Xanthophylls / Q000096:biosynthesis*
chemical_list: D010715:Phosphatidylglycerols; D024341:Xanthophylls; D002338:Carotenoids; C105515:echinenone