title: Thermoluminescence evidence for light-induced oxidation of tyrosine and histidine residues in manganese-depleted photosystem II particles.
abstract: In the thermoluminescence (TL) glow curve of photosystem II, particles depleted of manganese, a tyrosine modifier, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD) abolishes the TL band appearing around -55 degrees C (TL-55). Addition of a histidine modifier, diethylpyrocarbonate results in the disappearance of the band peaking around -30 degrees C (TL-30). NBD treatment also abolishes the EPR signal IIfast of oxidized tyrosine donor, Yz, and inhibits the electron transport from diphenylcarbazide to 2,6-dichlorophenol-indophenol. It is concluded that the TL-55 and TL-30 bands can be assigned to oxidized tyrosine (Yz+) and histidine (His+) residues, respectively, which participate in electron transfer from manganese to the reaction center of chlorophyll, P680+.
authors.affiliation: Institute of Soil Science and Photosynthesis, USSR Academy of Sciences, Puschchino, Moscow Region.
authors.forename: S I
authors.initials: SI
authors.lastname: Allakhverdiev
authors.forename: V V
authors.initials: VV
authors.lastname: Klimov
authors.forename: S
authors.initials: S
authors.lastname: Demeter
mesh_terms: D009327:4-Chloro-7-nitrobenzofurazan / Q000737:chemistry; D004047:Diethyl Pyrocarbonate / Q000737:chemistry; D004579:Electron Transport; D006639:Histidine / Q000378:metabolism*; D008027:Light; D045342:Light-Harvesting Protein Complexes; D049449:Luminescence; D008345:Manganese / Q000378:metabolism*; D010084:Oxidation-Reduction; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism*; D045332:Photosystem II Protein Complex; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D014443:Tyrosine; D008345:Manganese; D006639:Histidine; D009327:4-Chloro-7-nitrobenzofurazan; D004047:Diethyl Pyrocarbonate