BIOMIMETIC MODELING OF THE ACTIVE SITE OF [FE]-HYDROGENASE

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 研究中心，而研究中心不一定是研究者所在的机构。 Thauer最近的生化工作允许[Fe]-氢化酶活性位点的结构表征。这种氢化酶在某种意义上是独特的，它不像[FeFe]-和[NiFe]-氢化酶那样含有Fe-S簇。然而，它显示了一个共同的活性位点结构基序的存在下的双原子配体，这可能是一氧化碳。氢化酶是唯一含有这种对生物体有毒的配体的酶家族。我们提出了一系列的多边缘X射线吸收测量，以充分表征几个仿生化合物的电子和几何结构。我们的数据将允许改进的几个不确定性与活性位点的组成，电子和几何结构。此外，XANES和EXAFS数据将使我们能够验证电子结构计算方法，用于映射的H2-形成亚甲基四氢甲蝶呤脱氢酶的分子机制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Recent biochemical work by Thauer allowed for the structural characterization of the active site in [Fe]-hydrogenase. This hydrogenase is unique in a sense that it does not contain Fe-S clusters like the [FeFe]- and the [NiFe]-hydrogenases. However, it shows a common active site structural motif for the presence of diatomic ligands which is likely carbon monoxide. The hydrogenases are the only family of enzymes that contain this otherwise toxic ligand to living organisms. We are proposing a series of multi-edge x-ray absorption measurements to fully characterize the electronic and geometric structure of several biomimetic compounds. Our data will allow for the refinement of several uncertainties with the active site in composition, electronic, and geometric structure. Furthermore, the XANES and EXAFS data will allow us to validate electronic structure calculation methods that are to be used to map the molecular mechanism of the H2-forming methylenetetrahydromethanopterin dehydrogenase.