Yachandra V K, DeRose V J, Latimer M J, Mukerji I, Sauer K, Klein M P
Structural Biology Division, Lawrence Berkeley Laboratory, University of California, Berkeley 94720.
Science. 1993 Apr 30;260(5108):675-9. doi: 10.1126/science.8480177.
In the photosynthetic evolution of oxygen, water oxidation occurs at a catalytic site that includes four manganese atoms together with the essential cofactors, the calcium and chlorine ions. A structural model and a determination of the manganese oxidation states based on x-ray absorption spectroscopy are presented. The salient features, in both higher plants and cyanobacteria, are a pair of di-mu-oxo bridged manganese binuclear clusters linked by a mono-mu-oxo bridge, one proximal calcium atom, and one halide. In dark-adapted samples, manganese occurs in oxidation states (III) and (IV). Data from oriented membranes display distinct dichroism, precluding highly symmetrical structures for the manganese complex.
在光合放氧过程中，水氧化发生在一个催化位点，该位点包含四个锰原子以及必需的辅助因子钙和氯离子。本文给出了基于X射线吸收光谱的结构模型和锰氧化态的测定结果。在高等植物和蓝细菌中，其显著特征是一对由单μ-氧桥连接的双μ-氧桥联锰双核簇、一个近端钙原子和一个卤化物。在暗适应样品中，锰以氧化态（III）和（IV）存在。来自定向膜的数据显示出明显的二色性，排除了锰配合物具有高度对称结构的可能性。
