title: Phosphatidylcholine-induced reactivation of photosystem II membranes pretreated with Triton X-100.
abstract: Triton X-100-induced inactivation and phosphatidylcholine-induced reactivation of photosystem II (PSII) membranes were investigated using oxygen electrode, variable fluorescence and spectroscopic techniques including absorption and circular dichroism spectroscopy. Incubation of the PSII membrane with Triton X-100 reduced the oxygen-evolving rate, modified the variable chlorophyll fluorescence kinetics, changed the protein secondary structures, altered the chlorophyll binding state to proteins and decreased the excitonic interaction of chlorophyll molecules. Phosphatidylcholine addition did not change the protein secondary structures, but could partially reactivate the reduced oxygen-evolving rate, and partly reversed the variable fluorescence parameters, the chlorophyll binding state and the excitonic interaction of the chlorophyll molecules. The results indicate that the phosphatidylcholine environment can optimize the tertiary structures of PSII.
authors.affiliation: State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Ruan
authors.forename: Donghai
authors.initials: D
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu
authors.forename: Haibin
authors.initials: H
authors.lastname: Mao
authors.forename: Guofu
authors.initials: G
authors.lastname: Li
authors.forename: Yandao
authors.initials: Y
authors.lastname: Gong
authors.forename: Tingyun
authors.initials: T
authors.lastname: Kuang
authors.forename: Nanming
authors.initials: N
authors.lastname: Zhao
mesh_terms: D002734:Chlorophyll / Q000378:metabolism; D002942:Circular Dichroism; D003902:Detergents / Q000494:pharmacology*; D005453:Fluorescence; D045342:Light-Harvesting Protein Complexes; D017830:Octoxynol / Q000494:pharmacology*; D010100:Oxygen; D010713:Phosphatidylcholines / Q000494:pharmacology*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000187:drug effects*; D045332:Photosystem II Protein Complex; D013050:Spectrometry, Fluorescence / Q000379:methods; D018724:Spinacia oleracea
chemical_list: D003902:Detergents; D045342:Light-Harvesting Protein Complexes; D010713:Phosphatidylcholines; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D002734:Chlorophyll; D017830:Octoxynol; C017251:1,2-oleoylphosphatidylcholine; D010100:Oxygen