Electrogenicity accompanies photoreduction of the iron‐sulfur clusters FA and FB in photosystem I

FEBS Letters

Golbeck, John H²  Gourovskaya, Kira N¹  Sememov, Alexey Yu¹  Mamedov, Mahir D¹  Vassiliev, Ilya R² 

[1] Department of Photobiochemistry, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119899 Moscow, Russia;Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-310 Frear Laboratory, University Park, PA 16802-4500, USA

关键词: Proteoliposome;    Photosystem I;    Photoelectric response;    Electrogenicity;    Synechococcus sp. PCC 6301;   

DOI  :  10.1016/S0014-5793(98)00759-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Photovoltage responses accompanying electron transfer on the acceptor side of photosystem I (PS I) were investigated in proteoliposomes containing PS I complexes from the cyanobacterium Synechococcus sp. PCC 6301 using a direct electrometrical technique. The relative contributions of the F_X→F_B and the F_X→F_A electron transfer reactions to the overall electrogenicity were elucidated by comparing the sodium dithionite-induced decrease in the magnitude of the total photoelectric responses in control and in F_B-less (HgCl₂-treated) PS I complexes. The results obtained suggest that the electrogenesis on the acceptor side of PS I is related to electron transfers between both F_X and F_A and F_A and F_B. Based on the electrogenic nature of the latter reaction in PS I complexes, we conclude that F_A rather than F_B is the acceptor proximal to F_X.

【 授权许可】

Unknown