Environmental pH and a Glu364 to Gln mutation in the chlorophyll-binding CP47 protein affect redox-active TyrD and charge recombination in Photosystem II

FEBS Letters

article

Jaz N. Morris¹  Sándor Kovács³  Imre Vass³  Tina C. Summerfield¹  Julian J. Eaton-Rye² 

[1] Department of Botany, University of Otago;Department of Biochemistry, University of Otago;Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences

关键词: CP47;    cyanobacteria;    oxygen-evolving complex;    Photosystem II;    Synechocystis sp;    PCC 6803;    TyrD;    YD;   

DOI  :  10.1002/1873-3468.13307

来源: John Wiley & Sons Ltd.

【 摘 要 】

In Photosystem II, loop E of the chlorophyll-binding CP47 protein is located near a redox-active tyrosine, YD, forming a symmetrical analog to loop E in CP43, which provides a ligand to the oxygen-evolving complex (OEC). A Glu364 to Gln substitution in CP47, near YD, does not affect growth in the cyanobacterium Synechocystis sp. PCC 6803; however, deletion of the extrinsic protein PsbV in this mutant leads to a strain displaying a pH-sensitive phenotype. Using thermoluminescence, chlorophyll fluorescence, and flashinduced oxygen evolution analyses, we demonstrate that Glu364 influences the stability of YD and the redox state of the OEC, and highlight the effects of external pH on photosynthetic electron transfer in intact cyanobacterial cells.

【 授权许可】

Unknown