NON-HEME METALLO OXYGENASE CATALYSTS

含非血红素金属的加氧酶已被证明参与 哺乳动物和细菌中大量的代谢过程 系统。 我们计划的总体目标是继续分析 非血红素铁参与细菌的催化途径 双加氧酶、原儿茶酸-3,4-双加氧酶 (PCD) 和儿茶酚 双加氧酶（CTD），并与哺乳动物进行比较研究 非血红素铁单加氧酶、肝苯丙氨酸羟化酶 (PAH)、 哺乳动物铜单加氧酶、多巴胺-β-羟化酶 (DBH) 和 细菌非血红素铁单加氧酶、P. olevorans 环氧化酶/水解酶 （POEH）。 这些研究中使用的主要光谱技术是 扩展 X 射线吸收精细结构 (EXAFS) 光谱。 其中 具体目标是 (1) 使用 EXAFS 来识别性质、数量和 铁和铜结合配体的距离； (2) 检验 活性位点金属与底物、抑制剂、辅因子的相互作用， 和过渡态类似物； (3)借鉴我们的设计经验 通过检查新类别的化合物来研究过渡态类似物 模拟催化中间体，并捕获功能 参与催化和/或由于连接改变而被释放 在催化循环过程中。 我们建议获取的信息类型 对于理解非血红素金属的分子基础至关重要 加氧酶催化以及针对这些的特定效应器的设计 重要的酶。

Non-heme-metal-containing oxygenases have been shown to be involved in a large number of metabolic processes in both mammalian and bacterial systems. The broad objective of our program is to continue our analysis of the involvement of non-heme iron in the catalytic pathway of the bacterial dioxygenases, protocatechuate-3,4-dioxygenase (PCD), and catechol dioxygenase (CTD), and to carry out comparative studies with the mammalian non-heme iron monooxygenase, liver phenylalanine hydroxylase (PAH), the mammalian copper monooxygenase, dopamine-Beta-hydroxylase (DBH), and the bacterial non-heme iron monooxygenase, P. olevorans epoxidase/hydroylase (POEH). The major spectroscopic technique to be used in these studies is extended X-ray absorption fine structure (EXAFS) spectroscopy. Among the specific aims are (1) to use EXAFS to identify the nature, number, and distances of iron and copper-binding ligands; (2) to examine the interaction of active site metals with substrates, inhibitors, cofactors, and transition state analogs; (3) to draw on our experience in designing transition state analogs by examining new classes of compounds designed to mimic catalytic intermediates, and also to trap functionalities which participate in catalysis and/or are freed due to ligation alterations during the catalytic cycle. Information of the type we propose to obtain is essential to an understanding of molecular basis of non-heme metallo oxygenase catalysis and the design of specific effectors for these important enzymes.