MECHANISM OF STEROID ISOMERASE

类固醇异构酶的机制

• 批准号: 2179181
• 负责人: RALPH M POLLACK
• 金额: $ 22万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE COUNTY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-08-01 至 1995-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2179181
• 关键词: Pseudomonas; androstenedione; chemical binding; chemical kinetics; electron density; enzyme inhibitors; enzyme mechanism; enzyme structure; enzyme substrate; mutant; nuclear magnetic resonance spectroscopy; protein sequence; site directed mutagenesis; steroid delta isomerase; thermodynamics

The enzyme 3-oxo-delta5-steroid isomerase (KSI) is a key enzyme in the biosynthetic pathway for steroid hormones. the importance of steroid hormone deprivation protocols in current cancer therapy makes a detailed understanding of the mechanisms of the enzymes involved in this pathway of major importance. Ultimately, it is hoped that a selective inhibition of one of these enzymes will allow a pharmacological approach to hormone- dependent cancers to be achieved, surpassing current surgical methodology. This proposal for supplemental funding describes plans to investigate the 3-dimensional structure of the KSI from Pseudomonas testosteroni and its D38E mutant. These studies are required to enable us to correlate our kinetic and mechanistic results with the structure of the enzyme. Two- dimensional and three-dimensional NMR investigations will be carried out on 500 MHz and 600 MHz spectrometers and the results will be analyzed by NMR- based distance geometry methodologies. NMR studies will be extended to protein-inhibitor complexes to gain additional insights into structural aspects of catalysis. Preliminary data presented here show that this approach is feasible for the structural determination of KSI.

酶3-oxo-delta5-类固醇异构酶（KSI）是关键酶 类固醇激素的生物合成途径。 类固醇的重要性 当前癌症治疗中的激素剥夺方案使得详细 了解涉及此途径的酶的机制 主要的重要性。 最终，希望选择性抑制 这些酶之一将允许一种药理学方法来激素 - 要实现依赖的癌症，超过了当前的手术方法。 这项补充资金的建议描述了调查的计划 pseudomonas testosteroni及其ITS的KSI的3维结构 D38E突变体。 这些研究需要使我们能够关联我们的 动力学和机械结果与酶的结构。 二- 尺寸和三维NMR研究将在 500 MHz和600 MHz光谱仪将通过NMR-分析结果 基于距离几何方法。 NMR研究将扩展到 蛋白质抑制剂复合物以获得对结构的更多见解 催化的各个方面。 此处提供的初步数据表明 方法对于KSI的结构确定是可行的。