title: Reconstruction of the water-oxidizing complex in manganese-depleted Photosystem II using synthetic manganese complexes.
abstract: The efficiency of a trinuclear and two binuclear manganese complexes in reconstituting electron transport and O(2) evolution activity in Mn-depleted Photosystem II preparations is analyzed. The trinuclear Mn-complex is more efficient than two binuclear Mn-complexes in restoring oxygen evolution, but it is less effective as an electron donor than binuclear Mn-complexes. It is inferred from our results that recovery of electron transport and O(2) evolution with polynuclear Mn-complexes is affected with different factors. Moreover, the trinuclear Mn-complex is extremely sensitive to the addition of CaCl(2). It is suggested that there is an interaction between Ca(2+) and carboxyl within the trinuclear Mn-complex during photoactivation and this interaction benefits the ligation of Mn atom to the apo-WOC and form an active WOC. Binuclear Mn(III)Mn(III) complex shows slightly higher efficiency than binuclear Mn(III)Mn(IV) complex in restoration of O(2) evolution activity. The efficiency of three Mn-complexes in the reconstitution of WOC is in an order: trinuclear Mn(3)(III)>binuclear Mn(III)Mn(III)>binuclear Mn(III)Mn(IV).
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Guangye
authors.initials: G
authors.lastname: Han
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Guiying
authors.initials: G
authors.lastname: Chen
authors.forename: Lin
authors.initials: L
authors.lastname: Ling
authors.forename: Shuqin
authors.initials: S
authors.lastname: Li
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Khorobrykh
authors.forename: Sergei K
authors.initials: SK
authors.lastname: Zharmukhamedov
authors.forename: Vyacheslav V
authors.initials: VV
authors.lastname: Klimov
authors.forename: Tingyun
authors.initials: T
authors.lastname: Kuang
mesh_terms: D004579:Electron Transport; D007700:Kinetics; D008345:Manganese / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D010777:Photochemistry; D045332:Photosystem II Protein Complex / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D045332:Photosystem II Protein Complex; D014867:Water; D008345:Manganese; D010100:Oxygen