The mechanism of amine inhibition of the photosynthetic oxygen evolving complex

FEBS Letters

Sandusky, Peter O.¹  Yocum, Charles F.¹ 

[1] Division of Biological Sciences and Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109, USA

关键词: Photosystem II;    Oxygen evolution;    Amine inhibition;    Chloride;    Bridging ligand;    Signal IIf;    OEC;    oxygen evolving center;    PS;    photosystem;    Chl;    chlorophyll;    DCBQ;    2;    5-dichloro-p-benzoquinone;   

DOI  :  10.1016/0014-5793(83)80784-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Amines inhibit photosynthetic oxygen evolution by binding to manganese in the oxygen evolving complex. This inhibition is more effective if chloride is absent. Steady-state kinetic analyses show that ammonia and chloride compete for the same site in the oxygen evolving complex; inhibition of oxygen evolution by either chloride depletion or by ammonia addition induces Signal II_f, which saturates at high microwave power. These data indicate that chloride is bound at the manganese site in the oxygen evolving complex. We propose that the anion functions as a bridging ligand mediating electron transfer between manganese atoms and perhaps also between manganese and Z, the primary donor to P680.

【 授权许可】

Unknown