MODELING THE STRUCTURE AND REACTIVITY OF NI-HYDROGENASES

镍最近已被证明是几个关键组成部分， 维持某些生命过程的酶。 例如，在氢化酶中， （H2-ase），Ni密切参与促进电子转移到或 从H2 当与其他酶协同工作时，Ni H2-酶 最终用于电化学和化学能的相互转换， 自然界的基本过程。 拟议研究的重点将是 加深对倪在 金属酶H2-酶试图阐明 结构和功能。 需要回答的关键问题涉及蛋白质 环境稳定Ni（III），这是一种不寻常的氧化态， Ni对H2-催化反应的促进作用 阿塞。 该提案概述了设计一系列 合成的单核Ni络合物，其在富硫的 类似于H2-ase的“结合口袋”。 我们的方法是独一无二的， 我们设计了分子来提高反应性。 通过系统地 改变我们的模型复合物的结构， 这对（1）氧化还原行为和（2）反应性，我们应该能够 确定最适合稳定的环境 Ni（III）和促进与H2的反应性。

Nickel has recently been shown to be a critical component of several enzymes which sustain certain life processes. For example, in hydrogenase (H2-ase), Ni is intimately involved in promoting electron-transfer to or from H2. When operating in concert with other enzymes, Ni H2-ase ultimately serves to interconvert electrochemical and chemical energy - a fundamental process in nature. The focus of the proposed research will be to develop an increased understanding of the role played by Ni in the metalloenzyme H2-ase by attempting to elucidate the relationship between structure and function. Critical questions to be answered concern the ability of the protein environment to stabilize Ni(III), which is an unusual oxidation state for Ni, and the role that Ni plays in promoting the reactions catalyzed by H2- ase. The proposal outlines strategies used in the design of a series of synthetic mononuclear Ni complexes which contain Ni in a sulfur-rich "binding pocket" resembling that of H2-ase. Our approach is unique in that we have designed our molecules to promote reactivity. By systematically varying the structure of our model complexes and probing the effect that this has on (1) redox behavior and (2) reactivity, we should be able to identify the environment(s) with is(are) best suited for the stabilization of Ni(III) and promoting reactivity with H2.