RAPID KINETICS & OTHER STUDIES OF BIOLOGICAL OXYGENASES

快速动力学

• 批准号: 3270184
• 负责人: David P Ballou
• 金额: $ 20.16万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-09-01 至 1991-12-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3270184
• 关键词: Pseudomonas; X ray crystallography; catechols; chemical structure function; cytochrome P450; electron spin resonance spectroscopy; electron transport; enzyme complex; enzyme mechanism; enzyme structure; enzyme substrate; flavins; flavoproteins; fluorescence; iron; ligands; oxygenases; reduction; respiratory oxygenation

This project is an enzymological study aimed at determining the chemical mechanism whereby oxygen is activated by enzymes called oxygenases. Oxygenases are found in all aerobic organisms and are important in the biosynthesis, transformation, and degradation of steroids, nucleic acids, catecholamines, collagen, drugs, prostaglandins, lignin, and various foreign compounds. These enzymes are crucial to a majority of life forms. Our aims are to continue the investigation of three different types of oxygenases which we have isolated in homogeneous form: 1) Catechol dioxygenases, including catechol and protocatechuate dioxygenases, which are nonheme iron-containing enzymes important in the degradation of aromatic compounds by soil bacteria. 2) Flavoprotein hydroxylases which include bacterial and yeast enzymes such as para-hydroxybenzoate hydroxylase. 3) Phthalate oxygenase, a multicomponent dioxygenase system which converts an unactivated aromatic compound to a dihydrodiol. This type of oxygenase is very important in environmental control of aromatic compounds, and is poorly understood at present. The proposed study will employ rapid kinetics spectrophotometry, chemical quenching, and other enzymological methods. X-ray crystallography and genetic techniques, including cloning, gene sequencing and mutagenesis, will be used extensively to develop a better understanding of these interesting enzymes. We hope that results from these studies will lead to a better understanding of how molecular oxygen is activated for controlled metabolic processes. This in turn may lead to the ability to predict how various compounds will be metabolized in the environment.

该项目是一项酶学研究，旨在确定化学物质 氧被称为加氧酶的酶激活的机制。 加氧酶存在于所有需氧生物体中，并且在 类固醇，核酸， 儿茶酚胺，胶原蛋白，药物，木黄酮，木质素，以及各种 外来化合物 这些酶对大多数生命形式至关重要。 我们的目标是继续调查三种不同类型的 我们已经以同质形式分离的加氧酶：1）邻苯二酚 双加氧酶，包括儿茶酚和原儿茶酸双加氧酶， 是非血红素含铁酶的重要降解， 芳香化合物。 2)黄素蛋白羟化酶， 包括细菌和酵母酶，例如对羟基苯甲酸 羟化酶 3)邻苯二甲酸加氧酶，一种多组分双加氧酶系统 其将未活化的芳族化合物转化为二氢二醇。 这 加氧酶的类型在芳香族化合物的环境控制中非常重要 化合物，目前还知之甚少。 拟议的研究将采用快速动力学分光光度法，化学 猝灭和其它酶学方法。 x射线晶体学和 遗传技术，包括克隆、基因测序和诱变， 将被广泛使用，以更好地了解这些 有趣的酶 我们希望这些研究的结果将导致更好的理解 分子氧是如何被激活来控制代谢过程的 这反过来可能导致预测各种化合物将如何 在环境中代谢。