STRUCTURE OF TWO NIFE CLUSTERS IN CODH FROM CLOSTRIDIUM THERMOACETICUM

我们建议研究一氧化碳的两个Ni中心 来自热动梭菌的脱氢酶 使用Ni和Co K边EXAFS。 这项研究是由 最近发现用1，10-菲咯啉处理酶 仅从两个NiFe中心中的一个中除去Ni。 前EXAFS 对这种酶的研究还没有得出一个独特的结构决定 的NiFe集群，因为两个Ni网站不是 光谱上可区分的。 我们应该可以确定 用镍K边EXAFS研究邻菲咯啉的单中心结构 处理过的酶，并使用Co K-边的其他位点的结构 Co取代的菲咯啉处理的酶的EXAFS。

We propose to examine the two Ni centers of carbon monoxide dehydrogenase enzyme from Clostridium thermoacticum independently using Ni and Co K-edge EXAFS. This study is made possible by the recent discovery that treatment of the enzyme with 1,10-phenanthroline removes the Ni from only one of the two NiFe centers. Previous EXAFS work on this enzyme has not led to a unique structural determination of the NiFe clusters because the two Ni sites are not spectroscopically distinguishable. We should be able to determine the structure of one site using Ni K-edge EXAFS of the phenanthroline treated enzyme, and the structure of the other site using Co K-edge EXAFS of the Co substituted phenanthroline treated enzyme.