Molybdenum L-Edge XAS Spectra of MoFe Nitrogenase.
Molybdenum L-Edge XAS Spectra of MoFe Nitrogenase.
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DOI：
10.1002/zaac.201400446
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发表时间：
2015-01
影响因子：
1.4
通讯作者：
DeBeer S
中科院分区：
文献类型：
--
作者：
Bjornsson R;Delgado-Jaime MU;Lima FA;Sippel D;Schlesier J;Weyhermüller T;Einsle O;Neese F;DeBeer S
用X射线吸收光谱法研究了固氮酶天然蛋白和氧化蛋白以及Mo-Fe模型化合物的钼L边吸收光谱。最近收集的数据MoFe蛋白质（氧化和还原形式）相比，以前发表的Mo XAS数据在NMF溶液中的分离FeMo辅因子，并把最近的Mo K-边缘XAS研究的背景下，这表明了MoIII分配的钼原子FeMoco。在一个简单的配体场模型，从随时间变化的密度泛函理论（TDDFT）的方法，提出了一种方法，以提供进一步的见解钼L3边缘的分析内的L3边缘的数据进行解释。计算结果很好地再现了实验观察到的相对光谱趋势。最终，这些结果进一步支持MoIII在蛋白质结合的FeMoco以及分离的FeMoco中的分配。
A molybdenum L-edge X-ray absorption spectroscopy (XAS) study is presented for native and oxidized MoFe protein of nitrogenase as well as Mo-Fe model compounds. Recently collected data on MoFe protein (in oxidized and reduced forms) is compared to previously published Mo XAS data on the isolated FeMo cofactor in NMF solution and put in context of the recent Mo K-edge XAS study, which showed a MoIII assignment for the molybdenum atom in FeMoco. The L3-edge data are interpreted within a simple ligand-field model, from which a time-dependent density functional theory (TDDFT) approach is proposed as a way to provide further insights into the analysis of the molybdenum L3-edges. The calculated results reproduce well the relative spectral trends that are observed experimentally. Ultimately, these results give further support for the MoIII assignment in protein-bound FeMoco, as well as isolated FeMoco.