Structural-functional role of chloride in photosystem II.
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ABSTRACT:
SUBMITTER: Rivalta I
PROVIDER: S-EPMC3140697 | biostudies-literature | 2011 Jul
REPOSITORIES: biostudies-literature
Publications
Structural-functional role of chloride in photosystem II.
Rivalta Ivan I Amin Muhamed M Luber Sandra S Vassiliev Serguei S Pokhrel Ravi R Umena Yasufumi Y Kawakami Keisuke K Shen Jian-Ren JR Kamiya Nobuo N Bruce Doug D Brudvig Gary W GW Gunner M R MR Batista Victor S VS
Biochemistry 20110627 29
Chloride binding in photosystem II (PSII) is essential for photosynthetic water oxidation. However, the functional roles of chloride and possible binding sites, during oxygen evolution, remain controversial. This paper examines the functions of chloride based on its binding site revealed in the X-ray crystal structure of PSII at 1.9 Å resolution. We find that chloride depletion induces formation of a salt bridge between D2-K317 and D1-D61 that could suppress the transfer of protons to the lumen. ...[more]
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