BIOCHEMISTRY AND GENETICS OF MEMBRANE FUNCTIONS

膜功能的生物化学和遗传学

• 批准号: 3277548
• 负责人: JEN SHIANG HONG
• 金额: $ 17.05万
• 依托单位: BOSTON BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-12-01 至 1986-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3277548
• 关键词: Escherichia coli; Salmonella typhimurium; active transport; genetic mapping; glutamine; membrane permeability; membrane potentials; membrane structure; microorganism metabolism; molecular cloning; mutant; nucleic acid sequence; plasmids

We have shown previously that the ecf gene of E. coli is intimately associated with the active transport of amino acids and certain simple saccharides. Because of its importance in cellular processes, biochemical and genetic characterization of this energy coupling factor (ECF) will be pursued. The structural relationship of the ECF to beta-cystathionase will be investigated and elucidated at the nucleotide level, by DNA sequencing. Clones carrying both ecf and metC (cystathionase) gens have been isolated and will be used for these studies. Experiments are proposed to tackle the problem of the energetics of the osmotic shock-sensitive transport systems. Attempts will be made to identify the direct energy donor for these transport systems by finding the third reaction that makes acetyl phosphate and by investigating the fate of acetyl phosphate. The glutamine transport system of E. coli has been cloned using the plasmid pBR322. Using this, the genetic structure as well as the molecular organization of this transport system will be determined and elucidated. Reconstitution of glutamine transport will spheroplasts will be carried out with glutamine transport mutants as an in vitro complementation test to sort out the functional role of the transport components involved. The physiological effects of the glutamine transport defect on the catabolism of glutamate will be purused genetically in the initial phase, followed by biochemical study to find out what is the biochemical basis of the effect. The main objective of this research proposal is to broaden our knowledge concerning the molecular and genetic organization of the energy transduction machinery and the molecular mechanisms of the coupling of metabolic energy to active transport.

我们先前已经表明，大肠杆菌的ECF基因密切 与氨基酸的主动运输和某些简单相关 糖。 由于其在细胞过程中的重要性，因此 该能量耦合因子（ECF）的遗传表征将是 追捕。 ECF与β-环胱巩二酶的结构关系将 通过DNA测序在核苷酸水平上进行研究和阐明。 携带ECF和METC（胱胱氨酰化酶）Gens的克隆已经分离出来 并将用于这些研究。 提出了实验来解决 渗透冲击敏感运输的能量学问题 系统。 尝试确定直接能源供体的尝试 这些传输系统通过找到使乙酰基的第三个反应 磷酸盐并通过研究乙酰磷酸盐的命运。 谷氨酰胺 大肠杆菌的运输系统已使用质粒PBR322克隆。 使用它，遗传结构以及分子组织 该运输系统将被确定并阐明。 重组 谷氨酰胺的传输将使用谷氨酰胺进行。 转运突变体作为体外互补测试，以分类 涉及运输组件的功能作用。 生理 谷氨酰胺转运缺陷对谷氨酸分解代谢的影响 将在初始阶段进行遗传纯化，然后进行生化 研究以找出效果的生化基础是什么。 主 该研究建议的目的是扩大我们有关的知识 能量转导机械的分子和遗传组织 以及代谢能与活性偶联的分子机制 运输。