Structure and action of the N-oxygenase AurF from Streptomyces thioluteus
Structure and action of the N-oxygenase AurF from Streptomyces thioluteus
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DOI：
10.1016/j.jmb.2007.06.014
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发表时间：
2007-10-12
影响因子：
5.6
通讯作者：
Schulz, Georg E.
中科院分区：
文献类型：
--
作者：
Zocher, Georg;Winkler, Robert;Schulz, Georg E.
硝基存在于许多生物活性化合物中。它们大多是由氨基的逐步单氧作用产生的。其中一个涉及的酶是AurF，它参与了金葡萄素的生物合成。其结构在2.1埃分辨率下被确定为具有双核锰簇的同二聚体。酶制剂产生的分析晶体，在体外和体内都显示出活性。链折叠和簇与核糖核苷酸还原酶亚基R2和相关酶同源。通过异常x射线衍射确定了两种锰离子和约15%的铁含量。该簇与更常见的双铁簇的比较表明，在配位球中额外的组氨酸导致锰比铁的偏好。没有氧桥。底物对氨基苯甲酸酯被模拟成活性中心。该模型得到了突变体活性测量的支持。它显示了反应的几何形状，并解释了建立的底物光谱。(C) 2007 Elsevier Ltd.版权所有。
Nitro groups are found in a number of bioactive compounds. Most of them arise by a stepwise mono-oxygenation of amino groups. One of the involved enzymes is AurF participating in the biosynthesis of aureothin. Its structure was established at 2.1 angstrom resolution showing a homodimer with a binuclear manganese cluster. The enzyme preparation, which yielded the analyzed crystals, showed activity using in vitro and in vivo assays. Chain fold and cluster are homologous with ribonucleotide reductase subunit R2 and related enzymes. The two manganese ions and an iron content of about 15% were established by anomalous X-ray diffraction. A comparison of the cluster with more common di-iron clusters suggested an additional histidine in the coordination sphere to cause the preference for manganese over iron. There is no oxo-bridge. The substrate p-amino-benzoate was modeled into the active center. The model is supported by mutant activity measurements. It shows the geometry of the reaction and explains the established substrate spectrum. (C) 2007 Elsevier Ltd. All rights reserved.