The iron-site structure of [Fe]-hydrogenase and model systems: an X-ray absorption near edge spectroscopy study.
The iron-site structure of [Fe]-hydrogenase and model systems: an X-ray absorption near edge spectroscopy study.
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DOI：
10.1039/b922557a
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发表时间：
2010-03-28
期刊：
影响因子：
--
通讯作者：
Meyer-Klaucke W
中科院分区：
文献类型：
--
作者：
Salomone-Stagni M;Stellato F;Whaley CM;Vogt S;Morante S;Shima S;Rauchfuss TB;Meyer-Klaucke W
[Fe]-氢化酶是研究所有氢化酶催化中心共有的低自旋铁位点电子特性的理想系统。由于它们没有辅助的铁硫簇，并且具有包含单个铁中心的辅助因子，因此[Fe]-氢化酶非常适合对分子氢活化所需的那些因子进行光谱分析。具体来说，在这项研究中，我们通过对来自詹纳什甲烷球菌的[Fe]-氢化酶和五种模型复合物（Fe(乙二硫醇)-(CO)2(PMe3)2、[K(18-crown-6)]2[Fe(CN)2(CO)3]、K[Fe(CN)(CO)4]、 K3[Fe(iii)(CN)6]、K4[Fe(ii)(CN)6])。不同的电子给体对铁吸收K边能量位置有很大影响，这通常用于确定金属氧化态。我们的结果表明，用低自旋硫醇亚铁实现的 Fe(ii) 复合物的 K 边缘与来自詹纳什甲烷球菌的 [Fe]-氢化酶中的亚铁中心一致。金属几何形状也强烈影响 XANES 以及电子结构。使用计算机模拟，我们能够重现 XANES 光谱的主要特征，并描述单个供体贡献对光谱的影响。因此，我们揭示了来自辅因子酰基的不寻常碳供体在确定酶活性所需的电子结构中的重要作用。
The [Fe]-hydrogenase is an ideal system for studying the electronic properties of the low spin iron site that is common to the catalytic centres of all hydrogenases. Because they have no auxiliary iron-sulfur clusters and possess a cofactor containing a single iron centre, the [Fe]-hydrogenases are well suited for spectroscopic analysis of those factors required for the activation of molecular hydrogen. Specifically, in this study we shed light on the electronic and molecular structure of the iron centre by XAS analysis of [Fe]-hydrogenase from Methanocaldococcus jannashii and five model complexes (Fe(ethanedithiolate)-(CO)2(PMe3)2, [K(18-crown-6)]2[Fe(CN)2(CO)3], K[Fe(CN)(CO)4], K3[Fe(iii)(CN)6], K4[Fe(ii)(CN)6]). The different electron donors have a strong influence on the iron absorption K-edge energy position, which is frequently used to determine the metal oxidation state. Our results demonstrate that the K-edges of Fe(ii) complexes, achieved with low-spin ferrous thiolates, are consistent with a ferrous centre in the [Fe]-hydrogenase from Methanocaldococcus jannashii. The metal geometry also strongly influences the XANES and thus the electronic structure. Using in silico simulation, we were able to reproduce the main features of the XANES spectra and describe the effects of individual donor contributions on the spectra. Thereby, we reveal the essential role of an unusual carbon donor coming from an acyl group of the cofactor in the determination of the electronic structure required for the activity of the enzyme.
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影响因子：
16.6
作者：
Enthaler, Stephan;Junge, Kathrin;Beller, Matthias
通讯作者：
Beller, Matthias
影响因子：
2.5
作者：
Feiters, MC;Küpper, FC;Meyer-Klaucke, W
通讯作者：
Meyer-Klaucke, W
影响因子：
4.6
作者：
GOLDFIELD, SA;RAYMOND, KN
通讯作者：
RAYMOND, KN
影响因子：
3.7
作者：
PETTIFER, RF;BROUDER, C;LOPEZ, MFR
通讯作者：
LOPEZ, MFR
影响因子：
4.8
作者：
Pierik, AJ;Roseboom, W;Albracht, SPJ
通讯作者：
Albracht, SPJ