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.

我们之前已经表明，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。 由于其在细胞过程中的重要性，生化 该能量耦合因子（ECF）的遗传特征将是 被追击。 ECF 与 β-胱硫醚酶的结构关系将 通过DNA测序在核苷酸水平上进行研究和阐明。 已分离出携带 ecf 和 metC（胱硫醚酶）基因的克隆 并将用于这些研究。 建议进行实验来解决 渗透休克敏感运输的能量学问题 系统。 将尝试确定直接能源捐助者 这些运输系统通过找到产生乙酰基的第三个反应 磷酸盐并研究乙酰磷酸的命运。 谷氨酰胺 使用质粒 pBR322 克隆了大肠杆菌的转运系统。 利用这一点，遗传结构以及分子组织 该运输系统将被确定和阐明。 重构 谷氨酰胺运输将通过谷氨酰胺进行原生质球 运输突变体作为体外互补测试来筛选 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 在初始阶段将进行遗传研究，然后进行生化研究 研究找出该效应的生化基础是什么。 主要 这项研究计划的目的是扩大我们的知识 能量转换机制的分子和遗传组织 以及代谢能量与活性耦合的分子机制 运输。