An oxidative N-demethylase reveals PAS transition from ubiquitous sensor to enzyme
An oxidative N-demethylase reveals PAS transition from ubiquitous sensor to enzyme
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DOI：
10.1038/nature20159
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发表时间：
2016-11
期刊：
影响因子：
64.8
通讯作者：
M. Ortmayer;P. Lafite;B. Menon;T. Tralau;K. Fisher;L. Denkhaus;N. Scrutton;S. Rigby;A. Munro;Sam Hay;D. Leys
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文献类型：
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作者：
M. Ortmayer;P. Lafite;B. Menon;T. Tralau;K. Fisher;L. Denkhaus;N. Scrutton;S. Rigby;A. Munro;Sam Hay;D. Leys
通用的Per-ARNT-Sim（PAS）结构域作为信号转导模块起作用，其参与感测多种刺激，诸如小分子、光、氧化还原状态和气体。高度进化的PAS支架可以结合广泛的配体，包括血红素、黄素和金属离子。然而，虽然这些配体可以支持催化活性，据我们所知，没有酶PAS结构域已经found. Here，我们报告的第一个PAS酶的特性：一个血红素依赖oxidativeN-脱甲基酶。与其他胺氧化酶无关，这种酶含有血红素、黄素单核苷酸、2Fe-2S和四氢叶酸辅因子，并特异性催化二甲胺的NADPH依赖性氧化。α亚基的结构表明，它是一个血红素结合PAS结构域，结构类似于PAS气体传感器。二甲胺底物形成高度极化的氧结合位点的一部分，并通过充当电子和质子供体直接辅助氧活化。我们的数据显示，普遍存在的PAS结构域可以从传感器到酶的过渡，这表明PAS支架可以支持人工酶的发展。
The universal Per-ARNT-Sim (PAS) domain functions as a signal transduction module involved in sensing diverse stimuli such as small molecules, light, redox state and gases,. The highly evolvable PAS scaffold can bind a broad range of ligands, including haem, flavins and metal ions. However, although these ligands can support catalytic activity, to our knowledge no enzymatic PAS domain has been found. Here we report characterization of the first PAS enzyme: a haem-dependent oxidativeN-demethylase. Unrelated to other amine oxidases, this enzyme contains haem, flavin mononucleotide, 2Fe-2S and tetrahydrofolic acid cofactors, and specifically catalyses the NADPH-dependent oxidation of dimethylamine. The structure of the α subunit reveals that it is a haem-binding PAS domain, similar in structure to PAS gas sensors. The dimethylamine substrate forms part of a highly polarized oxygen-binding site, and directly assists oxygen activation by acting as both an electron and proton donor. Our data reveal that the ubiquitous PAS domain can make the transition from sensor to enzyme, suggesting that the PAS scaffold can support the development of artificial enzymes.