title: The redox state of plastoquinone pool regulates state transitions via cytochrome b6f complex in Synechocystis sp. PCC 6803.
abstract: The effects of benzoquinone analogues, phenyl-1,4-benzoquinone (PBQ) and 2,5-dibromo-3-methyl-6-isopropyl-1,4-benzoquinone (DBMIB), on state transitions in Synechocystis sp. PCC 6803 were investigated. PBQ induced a transition from state 2 to state 1 in the absence of actinic light whereas DBMIB caused a state 2 transition. 3-(3,4-Dichlorophenyl)-1,1-dimethyl urea could not eliminate the effects of PBQ and DBMIB. These results imply that the redox state of the plastoquinone pool controls the state transitions in vivo and cytochrome b6f complex is involved in this process. As a working hypothesis, we propose that the occupancy of the quinol oxidation site and the movement of the Rieske protein may be pivotal in this regulation.
authors.affiliation: State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, PR China.
authors.forename: Hai Bin
authors.initials: HB
authors.lastname: Mao
authors.forename: Guo Fu
authors.initials: GF
authors.lastname: Li
authors.forename: Xiang
authors.initials: X
authors.lastname: Ruan
authors.forename: Qing Yu
authors.initials: QY
authors.lastname: Wu
authors.forename: Yan Dao
authors.initials: YD
authors.lastname: Gong
authors.forename: Xiu Fang
authors.initials: XF
authors.lastname: Zhang
authors.forename: Nan Ming
authors.initials: NM
authors.lastname: Zhao
mesh_terms: D016227:Benzoquinones / Q000494:pharmacology; D000458:Cyanobacteria / Q000378:metabolism*; D003573:Cytochrome b Group / Q000378:metabolism*; D045346:Cytochrome b6f Complex; D003991:Dibromothymoquinone / Q000494:pharmacology; D008027:Light; D009097:Multienzyme Complexes / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D010971:Plastoquinone / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D016227:Benzoquinones; D003573:Cytochrome b Group; D009097:Multienzyme Complexes; D003991:Dibromothymoquinone; C029322:phenylbenzoquinone; D045346:Cytochrome b6f Complex; D010971:Plastoquinone