REGULATION OF GLUTAMATE SYNTHESIS IN BACILLUS SUBTILIS

枯草芽孢杆菌谷氨酸合成的调控

• 批准号: 2444621
• 负责人: ABRAHAM Lincoln SONENSHEIN
• 金额: $ 22.45万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-09-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2444621
• 关键词: Bacillus subtilis; DNA directed RNA polymerase; aconitate hydratase; aminoacid biosynthesis; bacterial genetics; citrates; enzyme activity; gene induction /repression; genetic promoter element; glutamate ammonia ligase; glutamates; intermolecular interaction; isocitrate dehydrogenase; malate dehydrogenase; microorganism culture; operon; phosphoproteins; site directed mutagenesis; transcription factor

The long-term goal of this project is to understand at the molecular level the mechanisms that control synthesis and activity of the enzymes that convert acetyl CoA to glutamate in Bacillus subtilis. This pathway, which is critical for generation of energy, reducing power, and biosynthetic building blocks, is also the junction between carbon and nitrogen metabolism and plays a key regulatory role in bacterial differentiation. Genes that encode the enzymes of this pathway, citrate synthase, aconitase, isocitrate dehydrogenase, and glutamate synthase, have all been cloned and have been shown to be regulated at the level of transcription. The specific aims of this project are to identify and isolate the proteins that regulate each of these genes, to deduce the intracellular metabolites that control activity of each regulatory protein and to reconstruct each regulatory system in vitro. One of these proteins has already been identified; GltC, the positive regulator of glutamate synthase synthesis, is a member of the LysR family. Since relatively little is known about how this family of proteins contacts DNA and stimulates transcription, the regions of GltC that contribute to DNA binding, effector binding, multimerization, and interaction with RNA polymerase will be targets for mutagenesis and genetic selection. The B. subtilis system is the primary paradigm for studies of Gram-positive bacteria and prokaryotic differentiation. Fundamental studies of B. subtilis gene expression, regulation of metabolism, and response to the environment are highly informative about the biology of related pathogenic bacteria and provide a means of studying issues of universal biological importance in an organism that is easily manipulated physiologically and genetically.

该项目的长期目标是在分子水平上了解 控制酶的合成和活性的机制 在枯草芽孢杆菌中将乙酰辅酶 A 转化为谷氨酸。 这条路，其中 对于能源产生、节能和生物合成至关重要 构建块，也是碳和氮之间的连接处 代谢并在细菌分化中发挥关键调节作用。 编码该途径的酶的基因，柠檬酸合酶， 乌头酸酶、异柠檬酸脱氢酶和谷氨酸合酶均已被 已被克隆并已被证明在转录水平上受到调节。 该项目的具体目标是鉴定和分离蛋白质 调节这些基因中的每一个，以推断细胞内代谢物 控制每个调节蛋白的活性并重建每个 体外调节系统。 其中一种蛋白质已经被 已确定； GltC，谷氨酸合酶合成的正调节因子， 是 LysR 家族的成员。 由于人们对此知之甚少 这个蛋白质家族如何接触 DNA 并刺激转录， GltC 区域有助于 DNA 结合、效应子结合、 多聚化以及与 RNA 聚合酶的相互作用将成为 诱变和遗传选择。 枯草芽孢杆菌系统是主要的 革兰氏阳性细菌和原核生物研究的范例 差异化。 枯草芽孢杆菌基因表达的基础研究， 新陈代谢的调节和对环境的反应都非常重要 有关相关病原菌的生物学信息并提供 一种研究具有普遍生物学重要性的问题的方法 易于在生理和遗传上操纵的有机体。