METABOLISM OF UNSATURATED AND HYDROXY FATTY ACIDS

不饱和脂肪酸和羟基脂肪酸的代谢

• 批准号: 2519274
• 负责人: HORST H SCHULZ
• 金额: $ 21.2万
• 依托单位: CITY COLLEGE OF NEW YORK
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-09-01 至 2000-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2519274
• 关键词: Escherichia coli; bioenergetics; cellular respiration; coenzyme A; enzyme mechanism; fatty acid metabolism; hydro lyase; hydroxy fatty acid; isomerase; laboratory rat; linolenate; microorganism metabolism; mitochondria; mutant; oleate; oxidation; oxidoreductase; peroxisome; respiratory enzyme; tissue /cell culture; transfection; unsaturated fatty acids

This project is designed to provide an in-depth understanding of the beta oxidation of unsaturated fatty adds, including polyunsaturated fatty adds. The focus of this study are the reactions and auxiliary enzymes which are specific to the beta-oxidation of unsaturated fatty acids. Most important is an investigation of the beta oxidation of unsaturated fatty adds with odd-numbered double bonds by the pathway involving delta 3,5, delta 2,4-dienoyl-CoA isomerase and 2,4-dienoyl CoA reductase. The contribution of this pathway to the mitochondrial beta-oxidation of 5- enoyl.CoA intermediates formed from linolenic add and oleic add will be determined. To facilitate such study with whole mitochondria, a mechanism-based inhibitor of delta 3,5, delta 2,4-dienoyl-CoA isomerase will be developed. The operation of this pathway in peroxisomes will be studied by determining the presence of delta 3,5, delta 2,4,-dienoyl-CoA isomerase in this organelle. The ongoing investigation of 2,4-dienoly-CoA reductase will be continued by cloning, sequencing and overexpressing the reductase gene from E. coli. The availability of a sufficent amount of the reductase will permit a study of its reaction mechanism. The substrate specificity of the peroxisomal reductase will be explored to aid in its purification. The notion that 3-hydroxyacyl-CoA epimerase may function in the metabolism of D-3-hydroxymyristic acid in E. coli will be investigated by isolating and characterizing epimerase mutants. The possible function of rat liver D-3-hydroxyacyl-CoA dehydratase, a peroxisomal enzyme essential for epimerase activity, in saturated fatty acid oxidation will be assessed by investigating its copurification with a suspected D-3-hydroxyacyl-CoA dehydrogenase. Finally the beta-oxidation of cis and trans unsaturated fatty acids in mitochondria will be compared with the aim of detecting and analyzing differences between their rates of degradation. This project will significantly increase the current knowledge of unsaturated fatty add beta-oxidation and thereby aid in the diagnosis of inherited diseases of fatty add oxidation and in assessing the metabolic consequences of trans fatty acid ingestion.

该项目旨在提供对测试版的深入了解 不饱和脂肪的氧化，包括多不饱和脂肪 补充道。本研究的重点是反应和辅助酶 它们是不饱和脂肪酸β-氧化所特有的。最多 重要的是对不饱和脂肪的β氧化的研究 通过涉及 delta 3,5 的途径添加奇数双键， δ 2,4-二烯酰辅酶A异构酶和2,4-二烯酰辅酶A还原酶。这 该途径对 5-线粒体 β-氧化的贡献 由亚麻酸和油酸形成的烯酰辅酶A中间体将是 决定。为了促进对整个线粒体的研究， 基于机制的 δ 3,5、δ 2,4-二烯酰辅酶 A 异构酶抑制剂 将被开发。该途径在过氧化物酶体中的运作将是 通过确定 δ 3,5、δ 2,4,-二烯酰辅酶 A 的存在进行研究 该细胞器中的异构酶。 2,4-二烯醇-CoA 的持续研究 还原酶将通过克隆、测序和过表达来继续 来自大肠杆菌的还原酶基因。足够数量的可用性 还原酶将允许研究其反应机制。这 将探索过氧化物酶体还原酶的底物特异性 帮助其纯化。 3-羟酰基-CoA 差向异构酶可能 D-3-羟基肉豆蔻酸在大肠杆菌中代谢的功能 通过分离和表征差向异构酶突变体进行研究。这 大鼠肝脏 D-3-羟酰基-CoA 脱水酶的可能功能 饱和脂肪中差向异构酶活性所必需的过氧化物酶体酶 将通过研究其与以下物质的共纯化来评估酸氧化： 可疑的 D-3-羟酰基-CoA 脱氢酶。最后进行β-氧化 将比较线粒体中顺式和反式不饱和脂肪酸的含量 目的是检测和分析其比率之间的差异 的退化。该项目将显着增加当前 了解不饱和脂肪添加β-氧化，从而有助于 脂肪氧化遗传性疾病的诊断和评估 摄入反式脂肪酸的代谢后果。