title: Photosystem II: the reaction center of oxygenic photosynthesis.
abstract: Photosystem II (PSII) uses light energy to split water into chemical products that power the planet. The stripped protons contribute to a membrane electrochemical potential before combining with the stripped electrons to make chemical bonds and releasing O2 for powering respiratory metabolisms. In this review, we provide an overview of the kinetics and thermodynamics of water oxidation that highlights the conserved performance of PSIIs across species. We discuss recent advances in our understanding of the site of water oxidation based upon the improved (1.9-Å resolution) atomic structure of the Mn4CaO5 water-oxidizing complex (WOC) within cyanobacterial PSII. We combine these insights with recent knowledge gained from studies of the biogenesis and assembly of the WOC (called photoassembly) to arrive at a proposed chemical mechanism for water oxidation.
authors.affiliation: Department of Chemistry and Chemical Biology and Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Vinyard
authors.forename: Gennady M
authors.initials: GM
authors.lastname: Ananyev
authors.forename: G Charles
authors.initials: GC
authors.lastname: Dismukes
mesh_terms: D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D000458:Cyanobacteria / Q000378:metabolism*; D007700:Kinetics; D008345:Manganese / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology*; D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000378:metabolism*; D013816:Thermodynamics; D014867:Water / Q000737:chemistry* / Q000378:metabolism
chemical_list: D045332:Photosystem II Protein Complex; D014867:Water; D008345:Manganese; D010100:Oxygen; D002118:Calcium