期刊
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
卷 6, 期 20, 页码 4825-4831出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/b407511k
关键词
-
We investigated the dependence of both the quantum yield of charge separation and pathways of charge recombination on the free energy level of the radical pair state P+Ph- in photosystem II. This was done by comparing the basal (F-0) fluorescence yield and the recombination rate of the S(2)Q(A)(-) state in various strains of Chlamydomonas reindhardtii in which the strength of a H-bond to the pheophytin bound to the D, subunit has been modified by site-directed mutagenesis. In agreement with previous results with homologous mutants in the cyanobacterium Synechocystis, the quantum yield decreased and the recombination Of S(2)Q(A)(-) was slowed down when the energy level of the radical pair was increased. The decreased quantum yield is analyzed in terms of a modified equilibrium between exciton and radical pair. The effects on the recombination rate confirm that in the wild type the process involves the P+Ph- state. Analysis of these results shows that, as in the case of Synechocystis, the energy level of the P+Ph- is less negative than currently thought by about 250 meV. An important consequence is a similar upward revision of the potential of the P+/P couple.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据