THE ACTIVE SITE OF [FE]- AND [NIFE]-HYDROGENASE

[FE]-和[NIFE]-氢化酶的活性位点

• 批准号: 8362261
• 负责人: WOLFRAM MEYER-KLAUCKE
• 金额: $ 0.08万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8362261
• 关键词: Active Sites; Affinity; Binding; Chemical Structure; Chemicals; Complex; Copper; Enzymes; Funding; Grant; Hydrogen; Hydrogenase; Ions; Iron; Lead; Molecular; National Center for Research Resources; Pathway interactions; Principal Investigator; Radiation; Reaction; Research; Research Infrastructure; Resources; Roentgen Rays; Site; Source; United States National Institutes of Health; absorption; cofactor; cost; electronic structure; hydroxypyridine; inhibitor/antagonist; iron hydrogenase; isocyanide; nickel-iron hydrogenase; structural biology

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. There are three phylogenetically different hydrogenases, [Fe]-, [NiFe]- and [FeFe]-hydrogenases, which catalyze activation of molecular hydrogen. [Fe]-hydrogenase is involved in hydrogenotrophic methanogenic pathway and harbors a unique iron-guanylyl pyridinol-cofactor. Its iron ion is complexed with two CO, one Cys-176-S, one N of the pyridinol ring and one acyl-C of the formyl-methyl substituent from the pyridinol ring. Crystal structure, chemical analysis, and infrared (IR)- and X-ray-absorption spectroscopic (XAS) analyses of this enzyme revealed the composition and geometry of the iron complex. However, to understand the detailed chemical- and electronic structures of the iron site in the catalytic reactions of [Fe]-hydrogenase, further analyses are required. One approach to this end is to analyze [Fe]-hydrogenase inhibited by its unique specific inhibitors. We have recently found that [Fe]-hydrogenase is inhibited by isocyanides, which are not known as the inhibitor of [NiFe]- and [FeFe]-hydrogenases. The affinity of these inhibitors is very high (Ki < 100 nM) (Shima et al. unpublished results). UV-Vis spectroscopic analysis indicated that isocyanides bind to the iron site. Fe K-edge XAS will characterize the coordination and electronic structure of the complex. Copper ions can also bind strongly to [Fe]-hydrogenase and inhibits this enzyme (Ki < 100 nM). These XAS analyses of [Fe]-hydrogenase-inhibitor complexes will lead to understanding of the mode of inhibition by these unique inhibitors.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 有三种系统发育不同的氢化酶[Fe] - ，[Nife] - 和[Fefe] - 氢化酶，它们催化了分子氢的激活。 [Fe] - 氢化酶参与氢化甲烷基途径，并拥有独特的铁甘烷基吡啶醇 - 合作醇。它的铁离子与两个COS，一个Cys-176-S，一个N吡啶醇环的一个N和一个来自吡啶醇环的甲基甲基取代基的N N。晶体结构，化学分析和红外（IR）和X射线吸收光谱（XAS）分析该酶揭示了铁络合物的组成和几何形状。但是，要了解[Fe]氢化酶的催化反应中铁位的详细化学和电子结构，需要进一步分析。一种目的的方法是分析其独特的特异性抑制剂抑制[Fe]氢化酶。我们最近发现，异氰酸酯抑制[Fe] - 氢化酶，这些异氰酸酯不称为[Nife]和[Fefe] - 氢化酶的抑制剂。这些抑制剂的亲和力非常高（Ki <100 nm）（Shima等人，未发表的结果）。 UV-VIS光谱分析表明异氰酸酯与铁位点结合。 Fe K边缘XAS将表征复合物的配位和电子结构。铜离子还可以与[Fe]氢化酶强烈结合并抑制该酶（Ki <100 nm）。 这些对[Fe] - 氢化酶抑制剂复合物的XAS分析将导致对这些独特抑制剂的抑制方式理解。