STRUCTURAL STUDIES OF BACTERIAL MULTICOMPONENT MONOOXYGENASES

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 细菌多组分单加氧酶(BMMS)，如甲烷单加氧酶(MMO)、甲苯/邻二甲苯单加氧酶(TOMO)和苯酚羟基酶(PH)等，催化饱和烃和芳香烃的区域和对映选择性氧化生成醇、酚、儿茶酚和环氧化物。在BMM羟基酶中，需要调节和还原酶蛋白质组分来实现催化作用，该羟基酶含有羧酸桥联的非血红素二铁活性部位，在这些活性部位上，氧气活化的中间产物形成并氧化碳氢化合物底物。通过对氙气加压、底物/产物浸泡以及Tomo羟基酶、PH羟基酶和羟基酶调节复合体突变形式的结晶学表征，探索BMMS和双铁羧酸盐蛋白的底物通路、质子和电子转移机制以及构效关系。这些数据将补充关于感兴趣蛋白质的生化结果，并提供额外的信息，以便与MMO系统进行比较，以阐明生物碳氢化合物氧化的机制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Bacterial multicomponent monooxygenases (BMMs) such as methane monooxygenase (MMO), toluene/o-xylene monooxygenase (ToMO), and phenol hydroxylase (PH) catalyze the regio- and enantioselective oxidation of saturated and aromatic hydrocarbons to yield alcohols, phenols, catechols, and epoxides. Regulatory and reductase protein components are required to effect catalysis in BMM hydroxylases, which contain carboxylate-bridged non-heme diiron active sites at which dioxygen-activated intermediates form and oxidize the hydrocarbon substrates. Crystallographic characterization of xenon-pressurized, substrate/product-soaked, and mutant forms of the ToMO hydroxylase and PH hydroxylase and hydroxylase-regulatory complex are sought to probe substrate access pathways, proton and electron transfer mechanisms, and structure-activity relationships in BMMs and diiron carboxylate protein in general. These data will complement biochemical findings on the proteins of interest and provide additional information for comparison with the MMO system in order to elucidate the mechanisms of biological hydrocarbon oxidation.