[铁铁]氢化酶的理论研究：合成模型的结构与红外光谱

Theoretical studies of [FeFe]-hydrogenase: structure and infrared spectra of synthetic models.

作者信息

Zilberman Silviu, Stiefel Edward I, Cohen Morrel H, Car Roberto

机构信息

Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.

出版信息

J Phys Chem B. 2006 Apr 6;110(13):7049-57. doi: 10.1021/jp056551z.

DOI:10.1021/jp056551z

PMID:16571021

Abstract

First-principles density functional theory calculations of synthetic models of [FeFe]-hydrogenase are used to show that the theoretical methods reproduce observed structures and infrared spectra to high accuracy. The accuracy is demonstrated for synthetic Fe(I)Fe(I) models ([(mu-PDT)Fe2(CO)6] and [(CN)(CO)2(mu-PDT)Fe2(CO)2(CN)]2-), for which we show that their infrared spectra are sensitive to the geometric arrangement of their CO/CN ligands and can be used in conjunction with quantum-mechanical total energies to predict the correct ligand geometry. We then analyze and predict the structure of mixed-valence Fe(II)Fe(I) models ([(mu-MeSCH2C(Me)(CH2S)2)Fe2(CO)4(CN)2]x-). These capabilities promise to distinguish among the various structural isomers of the enzyme's active site which are consistent with the limited accuracy of the X-ray observations.

摘要

对[FeFe]-氢化酶合成模型进行的第一性原理密度泛函理论计算表明，这些理论方法能够高精度地再现观测到的结构和红外光谱。对于合成的Fe(I)Fe(I)模型（[(μ-PDT)Fe2(CO)6]和[(CN)(CO)2(μ-PDT)Fe2(CO)2(CN)]2-），其准确性得到了证明。我们表明，它们的红外光谱对其CO/CN配体的几何排列敏感，并且可以与量子力学总能量结合使用来预测正确的配体几何结构。然后，我们分析并预测了混合价态Fe(II)Fe(I)模型（[(μ-MeSCH2C(Me)(CH2S)2)Fe2(CO)4(CN)2]x-）的结构。这些能力有望区分与X射线观测有限精度一致的酶活性位点的各种结构异构体。