Neidig Michael L, Solomon Edward I
Department of Chemistry, Stanford University, CA 94305, USA.
Chem Commun (Camb). 2005 Dec 21(47):5843-63. doi: 10.1039/b510233m. Epub 2005 Nov 16.
A large group of mononuclear non-heme iron enzymes exist which activate dioxygen to catalyze key biochemical transformations, including many of medical, pharmaceutical and environmental significance. These enzymes utilize high-spin Fe(II) active sites and additional reducing equivalents from cofactors or substrates to react with O2 to yield iron-oxygen intermediates competent to transform substrate to product. While Fe(II) sites have been difficult to study due to the lack of dominant spectroscopic features, a spectroscopic methodology has been developed which allows the elucidation of the geometric and electronic structures of these active sites and provides molecular level insight into the mechanisms of catalysis. This review provides a summary of this methodology with emphasis on its application to the determination of important active site structure-function correlations in mononuclear non-heme iron enzymes. These studies provide key insight into the mechanisms of oxygen activation, active site features that contribute to differences in reactivity and, combined with theoretical calculations and model studies, the nature of oxygen intermediates active in catalysis.
存在一大类单核非血红素铁酶，它们可激活双氧以催化关键的生物化学转化，包括许多具有医学、制药和环境意义的转化。这些酶利用高自旋Fe(II)活性位点以及来自辅因子或底物的额外还原当量与O2反应，生成能够将底物转化为产物的铁-氧中间体。由于缺乏主导的光谱特征，Fe(II)位点一直难以研究，但现已开发出一种光谱方法，可用于阐明这些活性位点的几何和电子结构，并提供催化机制的分子水平见解。本综述总结了该方法，重点介绍了其在确定单核非血红素铁酶中重要的活性位点结构-功能相关性方面的应用。这些研究为氧激活机制、导致反应性差异的活性位点特征提供了关键见解，并且与理论计算和模型研究相结合，揭示了催化中活性氧中间体的性质。
