MODE OF ACTION OF A BACTERIAL FUNCTION INVOLVED IN CELL GROWTH CONTROL

参与细胞生长控制的细菌功能的作用方式

• 批准号: 3813384
• 负责人: S GOTTESMAN
• 金额: --
• 依托单位: DIVISION OF CANCER BIOLOGY AND DIAGNOSIS
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3813384
• 关键词: Escherichia coli; adenosine triphosphate; bacterial genetics; biological signal transduction; cell capsule; cell growth regulation; chromosome translocation; enzyme biosynthesis; enzyme induction /repression; enzyme mechanism; enzyme structure; genetic mapping; membrane proteins; peptidases; protein degradation; protein sequence; protein structure function; proteolysis; regulatory gene; serine; ubiquitin

We have been studying the role that protein degradation plays in regulating cell growth control, through the study of the proteases which carry out ATP-dependent proteolysis in E. coli. The Lon protease degrades RcsA, a positive regulator of capsular polysaccharide synthesis, and SulA, a cell division inhibitor. We have demonstrated that RcsA interacts in the cell with another positive regulator, RcsB to promote efficient capsule synthesis. The Clp protease, a second major ATP-dependent protease, contains a large subunit, ClpA, with ATPase activity; this subunit has been well conserved in both other prokaryotic cells and eukaryotic cells. The smaller subunit, ClpP, contains the active site of the protease, and undergoes a self-processing reaction. The small subunit is also conserved in many cells. The structure and general organization of the Clp protease suggests that it has many similarities to the eukaryotic energy-dependent proteases which degrade ubiquitin-conjugated proteins. Alp, a third energy-dependent protease activity, which can substitute for Lon when overproduced, consists of a set of closely linked genes and a positive regulator. In another approach to the study of bacterial cell growth control, mutants which may be defective in partition of the bacterial chromosome have been selected, mapped and characterized.

我们一直在研究蛋白质降解在调节 细胞生长控制，通过研究蛋白酶， E.杆菌Lon蛋白酶降解RcsA， 荚膜多糖合成的正调节因子，和苏拉，一种细胞 分裂抑制剂我们已经证明了RcsA在细胞中相互作用， 与另一个积极的调节剂，RcsB，以促进高效胶囊 合成. Clp蛋白酶是第二种主要的ATP依赖性蛋白酶， 含有一个大亚基ClpA，具有ATP酶活性;该亚基已被 在其他原核细胞和真核细胞中都很保守。的 较小的亚基ClpP含有蛋白酶的活性位点，和 进行自我加工反应。小亚基也是保守的 在许多细胞中。Clp蛋白酶的结构和一般组织 这表明它与真核生物的能量依赖性有许多相似之处， 降解泛素结合蛋白的蛋白酶。阿尔普，第三个 能量依赖性蛋白酶活性，当 过度生产，由一组紧密相连的基因和一个积极的 调节器在另一种研究细菌细胞生长的方法中， 对照，在细菌的分配中可能有缺陷的突变体， 染色体已经被选择、绘制和表征。