GENETIC RESPONSE OF E COLI TO OZONE

描述 这个项目进一步描述了一个非常有趣的调节合奏 在首席调查员的实验室中发现了大肠杆菌。这 是一个氧化还原敏感的SoxRS系统，它由一个氧化还原传感器组成 SoxR蛋白和一个可诱导的近端激活子SOXS。在被以下对象氧化时 无论是超氧化物还是一氧化氮，SoxR都被激活，进而激活 袜子。SOXS诱导大量参与基因转录 抗氧化防御和抗生素抵抗力。在当前 调查人员希望确定另一项环境保护计划 重要的氧化剂臭氧触发了SOXRS系统。初步 在外国调查员实验室进行的实验表明， 事实上，SOXR是通过细胞暴露在臭氧中而激活的。进一步 计划进行实验，以表征时间和剂量- 这种激活的依赖性。另一组初步数据表明 维生素C和E对SoxRS系统有抑制作用。这 这一现象将在剂量依赖关系方面进行进一步研究。 关于SoxRS系统最有趣的观察之一是 它的激活导致了大肠杆菌对抗生素的耐药性。从这方面来说， 系统将在墨西哥臭氧激活的空气细菌中进行调查 城市。

DESCRIPTION This project further characterizes a very interesting regulating ensemble in E. coli discovered in the principal investigator's laboratory. This ensemble is a redox-sensitive SoxRS system which consists of a redox-sensor SoxR protein and an inducible proximal activator, SoxS. Upon oxidation by superoxide or nitric oxide, SoxR is activated and, in turn, it activates SoxS. SoxS induces transcription of a large number of genes involved in antioxidant defenses as well as antibiotic resistance. In the current proposal the investigators want to establish whether another environmentally important oxidant, ozone, triggers the SoxRS system. Preliminary experiments performed in the foreign investigator's laboratory showed that SoxR is, indeed, activated by the exposure of the cells to ozone. Further experiments are planned in order to characterize the time- and dose- dependence of this activation. Another set of preliminary data suggests that vitamins C and E have an inhibitory effect on the SoxRS system. This phenomenon will be investigated further with respect to dose-dependence. One of the most interesting observation made about the SoxRS system is that its activation leads to antibiotic resistance of E.coli. This aspect of the system will be investigated in ozone-activated airborne bacteria in Mexico City.