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.

我们以前已经证明，大肠杆菌的ecf基因与 与氨基酸的主动运输和某些简单的 糖类。由于它在细胞过程中的重要性，生化 而这种能量耦合因子(ECF)的遗传特征将是 被追捕。ECF与β-胱硫酮酶的结构关系 通过DNA测序，在核苷酸水平上进行研究和阐明。 同时携带ECF和METC基因的克隆已被分离 并将用于这些研究。建议进行实验，以解决 渗透激波敏感输运的能量学问题 系统。将努力确定直接能源捐赠者 这些运输系统通过寻找产生乙酰的第三个反应 并通过研究乙酰基磷酸盐的命运。谷氨酰胺 利用pBR322载体克隆了大肠杆菌的转运系统。 利用这一点，基因结构以及分子组织 这个运输系统将被确定和阐明。重组 谷氨酰胺转运球体将与谷氨酰胺一起进行 TRANSPORT突变体作为体外互补试验筛选 所涉及的运输组件的功能作用。生理学 谷氨酰胺转运缺陷对谷氨酸分解代谢的影响 将在最初阶段被遗传纯化，然后是生化 研究找出这种效果的生化基础是什么。主 这项研究提案的目的是拓宽我们对以下问题的认识 能量转导机制的分子和遗传组织 代谢能与活性偶联的分子机制 运输。