A growing subset of metalloenzymes activates dioxygen with nonheme diiron active sites to effect substrate oxidations that range from the hydroxylation of methane and the desaturation of fatty acids to the deformylation of fatty aldehydes to produce alkanes and the six-electron oxidation of aminoarenes to nitroarenes in the biosynthesis of antibiotics. A common feature of their reaction mechanisms is the formation of O₂ adducts that evolve into more reactive derivatives such as diiron(II,III)-superoxo, diiron(III)-peroxo, diiron(III,IV)-oxo, and diiron(IV)-oxo species, which carry out particular substrate oxidation tasks. In this review, we survey the various enzymes belonging to this unique subset and the mechanisms by which substrate oxidation is carried out. We examine the nature of the reactive intermediates, as revealed by X-ray crystallography and the application of various spectroscopic methods and their associated reactivity. We also discuss the structural and electronic properties of the model complexes that have been found to mimic salient aspects of these enzyme active sites. Much has been learned in the past 25 years, but key questions remain to be answered.

中文翻译：

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非血红素铁蛋白酶的双氧激活：不同的双氧加合物，高价中间体和相关的模型配合物

不断增长的金属酶子集会激活具有非血红素二铁活性位点的双氧，从而影响底物氧化，从甲烷的羟基化和脂肪酸的去饱和到脂肪醛的甲酰化以生成烷烃，以及氨基芳烃的六电子氧化为硝基芳烃。抗生素的生物合成。它们的反应机理的共同特征是O ₂的形成演变成反应性更高的衍生物的加合物，例如二铁（II，III）-超氧，二铁（III）-过氧，二铁（III，IV）-氧和二铁（IV）-氧的物种，它们执行特定的底物氧化任务。在这篇综述中，我们调查了属于该独特子集的各种酶以及进行底物氧化的机制。我们检查了反应中间体的性质，如X射线晶体学以及各种光谱方法的应用及其相关的反应性所揭示。我们还讨论了已发现可模拟这些酶活性位点显着方面的模型复合物的结构和电子性质。在过去的25年中，我们学到了很多东西，但是关键的问题仍然有待回答。