A Short Review on EPR Studies on the Mechanism of Photosynthetic Water Splitting

Abstract

Abstract:

In oxygenic photosynthesis, photosystem II (PSII) catalyzes the water splitting/oxidation and O₂ release into the ambient atmosphere upon light absorption. The catalytic active site therein is an inorganic cluster consisted of 4 Mn, 1 Ca and 5 O. Electron paramagnetic resonance (EPR) spectroscopy plays a key role in the endeavor to elucidate the mechanism of water splitting. In this short review, we emphasized the interpretation of EPR spectra originating from different oxidized Mn₄O₅Ca clusters and from different magnetic interactions between the Mn₄O₅Ca cluster and a nearby tyrosine radical, combined with the methanol effects. The overall oxidation of two substrate water molecules is a stepwise and protoncoupled electron transfer.

Key words: Mn₄O₅Ca cluster, electron paramagnetic resonance spectroscopy, photosynthesis, water splitting

CLC Number:

O482.53

ZHOU Jing-Wei, CHEN Ming, SU Ji-Hu, DU Jiang-Feng. A Short Review on EPR Studies on the Mechanism of Photosynthetic Water Splitting[J]. Chinese Journal of Magnetic Resonance, 2011, 28(4): 502-511.

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