光合作用氧释放机理研究进展

植物在光合作用过程中不仅为同化CO2提供能量和还原力，同时裂解水放出氧气。放氧反应主要由光系统Ⅱ(PSⅡ)氧化侧的4个锰原子组成的锰簇催化完成的。因此，锰簇在光合放氧过程中起看至关重要的作用。文章概述了对锰簇及其微环境的结构和功能的研究进展。

Progressive Investigation on the Molecular Mechanism of Photosynthetic Oxygen Evolution

In green plants, oxygen is released as a byproduct of photosynthesis, providing the oxidising power required for biological energy utiligation in many organisms including human. Photosystem II, responsible for water oxidation and oxygen evolution, locates at the starting of the whole photosynthetic electron transfer chain. It uses light energy to generate sufficient oxidizing power to extract electrons from water, and then transfers electrons to the plastoquinone pool. At the donor side of Photosystem II, a manganese cluster composed of four manganese atoms plays a crucial role in oxygen evolution, to connect the univalent generator of oxi- dant to the device for extracting four electrons from water. TyrZ, the 161 tyrosine of D1 protein, transferring electrons from Mn cluster to primary electron donor, also plays an important role in oxygen evolution. Extrinsic proteins, Ca 2+ and Cl - located at the donor side are necessary for oxygen evolution under normal conditions. In this review, the progress in the research of the structure and function of manganese cluster and other cofactors is presented.