S I Allakhverdiev, M S Karacan, G Somer, N Karacan, E M Khan, S Y Rane, S Padhye, V V Klimov, G Renger
{"title":"Binuclear manganese (III) complexes as electron donors in D1/D2/cytochrome b559 preparations isolated from spinach photosystem II membrane fragments.","authors":"S I Allakhverdiev, M S Karacan, G Somer, N Karacan, E M Khan, S Y Rane, S Padhye, V V Klimov, G Renger","doi":"10.1515/znc-1994-9-1008","DOIUrl":"https://doi.org/10.1515/znc-1994-9-1008","url":null,"abstract":"<p><p>The capability of different manganese complexes to act as PS II electron donors in D1/D2/cytochrome b559 complexes has been analyzed by measuring actinic light-induced absorption changes at 680 nm (650 nm) and 340 nm, reflecting the photoaccumulation of Pheophytin⁻ (Pheo⁻) and the reduction of NADP⁺, respectively. The data obtained revealed: a) the donor capacity of synthetic binuclear Mn (III)₂complexes containing aromatic ligands significantly exceeds that for MnCl₂ in both cases, i.e. Pheo⁻ photoaccumulation and NADP⁺ reduction; b) manganese complexes can serve as suitable electron donors for light-induced NADP⁺ reduction catalyzed by D1/D2/cytochrome b559 complexes and ferredoxin plus ferredoxin-NADP⁺ reductase under anaerobic conditions and c) the specific turnover rate of the system leading to NADP⁺ reduction is extremely small. The implications of these findings are briefly discussed.</p>","PeriodicalId":520830,"journal":{"name":"Zeitschrift fur Naturforschung. C, Journal of biosciences","volume":" ","pages":"587-92"},"PeriodicalIF":2.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znc-1994-9-1008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30995806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}