Flash‐photolysis studies of the electron transfer from genetically modified spinach plastocyanin to photosystem I

FEBS Letters

Young, Simon¹  Nordling, Margareta¹  Sigfridsson, Kalle¹  Lundberg, Lennart G.¹  Hansson, Örjan¹ 

[1] Department of Biochemistry and Biophysics, Chalmers University of Technology and University of Göteborg, S-412 96 Göteborg Sweden

关键词: Electron transfer;    Flash photolysis;    Plastocyanin;    Photosynthesis;    Photosystem I;    Site-directed mutagenesis;    ET;    electron transfer;    P700;    reaction-center chlorophyll;    Pc;    plastocyanin;    PCR;    polymerase chain reaction;    PSI;    photosystem I;    Tris;    2-amino-2-hydroxymethylpropane-1;    3-diol;   

DOI  :  10.1016/0014-5793(91)81313-W

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Plastocyanin (Pc) has been modified by site-directed mutagenesis at two separate electron-transfer (ET) sites: Leu-12-Glu at a hydrophobic patch, and Tyr-83-His at an acidic patch. The reduction potential at pH 7.5 is decreased by 26 mV in Pc(Leu-12-Glu) and increased by 35 mV in Pc(Tyr-83-His). The latter mutant shows a 2-fold slower intracomplex ET to photosystem I (PSI) as expected from the decreased driving force. The affinity for PSI is unaffected for this mutant but is drastically decreased for Pc(Leu-12-Glu). It is concluded that the hydrophobic patch is more important for the ET to PSI.

【 授权许可】

Unknown