X-RAY CRYSTALLOGRAPHIC STUDIES OF METAL-REQUIRING ENZYMES

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 我们在NE-CAT的工作集中在一些金属酶系统上，对于这些系统，晶体质量和大小使得他们在其他同步加速器源上的研究变得困难。该实验室的一个关键项目专注于双核锰金属酶精氨酸酶，以及共享精氨酸酶折叠的酶，如锌酶人组蛋白脱乙酰基酶-8和细菌乙酰多胺氨基水解酶。这项工作还包括来自小肠结肠耶尔森菌的锌依赖脱乙酰酶LpxC，它催化革兰氏阴性细菌合成脂质A的第一步。对这些金属酶的比较将最终揭示精氨酸酶折叠中金属离子专一性和化学计量比差异进化的化学和结构基础。此外，我们在NE-CAT的工作重点是萜类环化酶。这些都是需要金属的酶，催化生物中最复杂的有机化学反应。具体地说，我们的工作集中在催化涉及底物法尼基二磷酸或香叶基二磷酸的环化反应的倍半萜环化酶：EPI-异氮杂烯合成酶和铜酰二磷酸合成酶。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Our work at NE-CAT has focused on a number of metalloenzyme systems for which crystal quality and size make their study difficult at other synchrotron sources. A key project in the lab focuses on the binuclear manganese metalloezyme arginase, as well as enzymes that share the arginase fold such as the zinc enzymes human histone deacetylase-8 and bacterial acetylpolyamine amidohydrolase. This work additionally includes the zinc-dependent deacetylase LpxC from Yersinia enterocolitica, which catalyzes the first committed step of lipid A biosynthesis in Gram-negative bacteria. Comparisons of these metalloenzymes will ultimately reveal the chemical and structural basis for the divergent evolution of metal ion specificity and stoichiometry in the arginase fold. Additionally, our work at NE-CAT has focused on terpenoid cyclases. These are metal-requiring enzymes that catalyze the most complex organic chemical reactions in biology. Specifically, our work has focused on sesquiterpene cyclases that catalyze cyclization reactions involving substrates farnesyl diphosphate or geranylgeranyl diphosphate: epi-isozizaene synthase and copalyl diphosphate synthase.