Activation of Alternative Electron Transfer in PS Ⅱ by Inhibition of Proton Transfer at the Acceptor Side

摘要

Cd2+, Zn2+ and Cu2+ have expressed effect on QB protonation and reduction in bacterial reaction centers (BRC) (Utschig et ah, 2001). This work is dedicated to investigating influence of Cd2+, Pb2+, Hg2+, Zn2+, and Cu2+ at the level of acceptor side of Photosystem Ⅱ (PS Ⅱ). Light-dependent proton uptake decreased in the presence of 80 μM Cu2+ by 90%, and of 200 μM Zn2+-by 70%. At that, considerable reductions of electron transport rate were not observed. In the concentration range of 50-200 μM Cu2+ and Cd2+ caused an insignificant growth of