STRUCTURE AND FUNCTION OF MYELOPEROXIDASE

髓过氧化物酶，一种中性粒细胞的血红素酶，将被 通过各种光谱手段进行提纯和检验。特价 髓过氧化物酶的特点是它能够催化 卤化物离子，如氯离子、溴离子和碘离子的氧化 过氧化氢作用下的次卤酸盐杀死被摄取的有机体。自.以来 血红素基团是这种酶的活性中心，其电子性质 亚铁血红素的组成、亚铁血红素基团的环境以及 底物结合(特别是氯离子)对这些特性的影响 阐明是为了获得有关这一机制的重要信息 酶的作用。这项建议的主要目标是：(1) 氯结合部位的测定，(2)表征 血红素基团的结构，(3)模式的确定 血红素基团与脱脂蛋白分子量之间的相互作用，以及(4) 用系统评价法评价血红素组间的不等价性 光吸收、电子顺磁共振、质子吸收的利用 和氯-核磁共振、共振拉曼散射，以及 动力学光谱分析。阐明其致病的分子机制 髓过氧化物酶的作用对于我们理解 多核白细胞的杀菌功能，这对 哺乳动物物种抵抗细菌感染的生存能力。

Myeloperoxidase, a heme enzyme of polymorphonuclear neutrophils, will be purified and examined by a variety of spectroscopic means. Special characteristics of myeloper-oxidase is its ability to catalyze the oxidation of halide ion, such as chloride, bromide, and iodide ions, to hypohalite by hydrogen peroxide to kill the ingested organism. Since the heme group is the active center of this enzyme, the electronic properties of the heme irom, the environment of the heme group, and the effect of substrate binding (particularly chloride ion) on these properties will be elucidated in order to obtain the vital informations about the mechanism of action of the enzyme. The primary goals of this proposal are: (1) determination of the chloride binding site, (2) characterization of the structure of the heme group, (3) determination of the mode of the interactions between the heme group and apo-protein moeity, and (4) evaluation of the inequivalence between the heme groups by systematic utilization of light absorption, electron paramagentic resonance, proton- and chlorine-nuclear magnetic resonance, resonance Raman scattering, and kinetic spectroscopies. Elucidation of the molecular mechanism of the enzyme action of myeloperoxidase is essential for our understanding the bacteriocidal function of polymophonuclear leukocytes, which is vital for survival of mammalian species against bacterial infections.