颗粒裂解肽G13结构域引发细菌SOS反应

摘要

Objective By using self-luminous lux gene as a reporter gene we detected the effects of G13 domain of granulysin on the expression of the reporter gene under the control of the SOS promoter.Methods We got pBAD-G13 engineering bacteria and Salmonella typhimurium Sa194 mixed culture, and selected a specific time to measure RLU and A600 values.We calculated RLU of the units of bacteria according to the formula.Results We showed that recombinant G13 domain did induce the expression of the reporter gene, and the expression level was time-dependent and took on the form of a peak curve.At about 4 min of induction, the expression level of the reporter gene reached its peak, and then gradually decreased.Conclusions The recombinant G13 domain triggered the degradation of the repressor protein LexA, and induced SOS response in the bacterial cells.%目的 利用自发光lux基因作为报告基因,检测颗粒裂解肽G13结构域对SOS启动子控制下的报告基因表达的影响.方法 pBAD-G13工程菌和鼠伤寒沙门菌Sa194混合培养,选取特定时间点测晕混合菌液的光吸收值和A600值,通过公式运算,计算其单位细菌产生的平均光吸收值.结果 重组G13结构域可诱导报告基因的表达,且诱导表达的水平具时间效应,呈现峰型图,在处理的开始阶段(4min左右)lux基因被强烈诱导表达并且达到峰值,随后lux基因表达水平逐渐平缓下降.结论 重组G13结构域引起细菌内SOS操纵子阻遏蛋白LexA蛋白的降解,诱导发生SOS反应.