Barber James, Murray James W
Division of Molecular Biosciences, Imperial College London, London SW7 2AZ, UK.
Philos Trans R Soc Lond B Biol Sci. 2008 Mar 27;363(1494):1129-38; discussion 1137-8. doi: 10.1098/rstb.2007.2208.
The location, structure and protein environment of the Mn4Ca2+ cluster, which catalyses the light-driven, water-splitting reaction of photosystem II, has been revealed by X-ray crystallography. However, owing to the low resolutions of the crystal structures reported to date, and the possibility of radiation damage at the catalytic centre, the precise position of each metal ion remains unknown. To some extent, these problems have been overcome by applying spectroscopic techniques like extended X-ray absorption fine structure. Taking into account the most recent results obtained with these two X-ray-based techniques, we have attempted to refine models of the structure of the Mn4Ca2+ cluster and its protein environment.
通过X射线晶体学已揭示了催化光系统II光驱动水裂解反应的Mn4Ca2+簇的位置、结构和蛋白质环境。然而,由于迄今为止报道的晶体结构分辨率较低,以及催化中心存在辐射损伤的可能性,每个金属离子的确切位置仍然未知。在某种程度上,通过应用诸如扩展X射线吸收精细结构等光谱技术,这些问题已得到克服。考虑到用这两种基于X射线的技术获得的最新结果,我们已尝试完善Mn4Ca2+簇及其蛋白质环境的结构模型。