MAGNETIC CHARACTERIZATION OF THE WATER OXIDIZING ENZYME

这项工作的目的是了解水是如何被氧化的。 在光合作用的有机体中转化为氧气。所有人的健康 包括人类在内的需氧生物严重依赖于此。 进程，因为它是唯一重要的全球资源 生物圈中的大气氧气。我们试图找出 在此过程中形成的化学中间体的结构 四步，酶促反应。和的结构 四种锰离子在生物活性中的作用 网站是本研究的主要目标。我们介绍两个 以前未曾探索过的研究水的物理方法 光合作用膜中的氧化部位。一共有三个 提出的研究课题：1)时间分辨磁学 在此过程中形成的化学中间体的敏感性 光合作用膜中水氧化部位的周转， 2)EPR和Endor光谱分析的应用 测定土壤中结合锰的蛋白质氨基酸 酶簇的活性部位，以及3)取代 其他金属离子作为一种结构和机制的锰 光合作用中水氧化反应的探讨 膜。

The objective of this work is to understand how water is oxidized to from oxygen in photosynthetic organisms. The health of all aerobic organisms, including man, is critically dependent upon this process because it is the only significant global source of atmospheric oxygen in the biosphere. We seek to identify the structures of the chemical intermediates that form during this four step, enzyme catalyzed reaction. The structures of and the roles played by four manganese ions which function at the active site are the key objectives of this research. We introduce two previously unexplored physical methods for studying the water oxidizing site in photosynthetic membranes. There are three proposed topics of research: 1) time resolved magnetic susceptibility of the chemical intermediates which form during turnover of the water oxidizing site in photosynthetic membranes, 2) the application of EPR and ENDOR spectroscopies for determining the protein amino acids which bind manganese in the active site of the enzymatic cluster, and 3) the substitution of manganese by other metal ions as a structural and mechanistic probe of the water oxidizing reaction in photosynthetic membranes.