RpoS和cAMP-CRP对大肠杆菌抗酸系统1的调控研究

Enteric bacteria are important to human life and health. They have to pass through the extremely acidic stomach before entering the more hospitable gastro-intestinal tract. The specific mechanism of acid resistance 1 (AR1) in Escherichia coli is still unclear. Research shows that, the transcription factor RpoS and cAMP-CRP participate in the regulation of AR1 system. F1Fo-ATPase also plays a very important role, but the specific function mechanism and regulation of F1Fo-ATPase is not clear. We found that metabolic processes that require ATP participate in survival under extremely acidic conditions, and that one such system is the ATP-dependent DNA repair system. The previous studies found that, the electron transport chain and F1Fo-ATPase play an important role in Escherichia coli acid resistance mechanis and the double gene mutant can't survival at acidic condition. This project aims to further research on AR1 system, investigating the specific regulation mechanism of AR1 system by RpoS and cAMP-CRP in E.coli and whether the F1Fo-ATPase is regulated by these regulators or not. This project will provide novel insights into the mechanism of bacterial AR1.

肠道细菌与人类生活和健康息息相关, 它们必须通过极酸的胃部环境才能到达相对适宜生存的肠道系统。大肠杆菌抗酸系统1(AR1)的机制至今尚不清楚, 研究表明调控因子RpoS和cAMP-CRP参与AR1的调控，此外, F1Fo-ATPase也起非常重要的作用, 但该系统的调控机制以及作用方式仍不清楚。 我们发现了ATP代谢途径在抗酸系统中起重要作用, 其中ATP依赖的DNA修复系统在抗酸机制中发挥作用。 前期工作发现电子传递链和F1Fo-ATPase的双突变株在极酸环境下不能存活, 表明氧化磷酸化系统在大肠杆菌抗酸机制中起重要作用。本项目拟对AR1进行挖掘研究，探索RpoS和cAMP-CRP在AR1中的具体调控机制以及是否通过调控F1Fo-ATPase对AR1起作用。通过对肠道细菌AR1调控机制的研究，为深入研究细菌的抗酸机制奠定基础。

肠道细菌与人类生活和健康息息相关, 它们必须通过极酸的胃部环境才能到达相对适宜生存的肠道系统。大肠杆菌抗酸系统1(AR1)的机制至今尚不清楚, 研究表明调控因.子RpoS 和cAMP-CRP 参与AR1 的调控，此外, F1Fo-ATPase 也起非常重要的作用, 但该系统的调控机制以及作用方式仍不清楚。 我们发现了ATP 代谢途径在抗酸系统中起重要作用, 其中ATP 依赖的DNA 修复系统在抗酸机制中发挥作用。 前期工作发现电子传递链和F1Fo-ATPase 的双突变株在极酸环境下不能存活, 表明氧化磷酸化系统在大肠杆菌抗酸机制中起重要作用。本项目对AR1 进行挖掘研究，发现了ATP浓度在弱酸性环境下增加主要通过糖酵解途径，并发现RpoS以及CRP主要在酸性条件下控制部分基因的表达下调。通过对肠道细菌AR1 调控机制的研究，为深入研究细菌的抗酸机制奠定基础。