CodY在单核细胞增生李斯特菌运动和毒力方面的作用

发布时间：2019-05-06 11:40

【摘要】：目的:探究全局性转录调控因子CodY在单核细胞增生李斯特菌(Listeria monocytogenes,Lm)鞭毛运动和细菌毒力方面的作用。方法:通过同源重组的方法敲除Lm染色体上CodY的编码基因codY并成功构建缺失菌株的回复菌株;利用平板泳动法观测鞭毛运动的变化,RT-qPCR检测与鞭毛运动相关基因的转录表达;比较野生型菌株EGDe与CodY缺失菌株对细菌溶血活性、棉铃虫幼虫的半致死剂量和主要的毒力因子LLO和毒力基因调控蛋白PrfA转录表达的影响。结果:同野生型菌株相比,CodY缺失菌株鞭毛运动和相关基因,以及主要的毒力因子LLO和PrfA的转录表达显著降低(P≤0.01),溶血活性显著降低(P≤0.01),对棉铃虫幼虫的半致死剂量上升了5.8倍。结论:CodY在Lm鞭毛运动和细菌毒力调控方面具有重要作用。
[Abstract]:Aim: to investigate the role of global transcription regulator CodY in flagellum movement and virulence of Listeria monocytogenes (Listeria monocytogenes,Lm). Methods: the homologous recombination method was used to knock out the coding gene codY of CodY on the chromosome of Lm and successfully construct the replicating strain of the deleted strain. The changes of flagellum movement were observed by plate electrophoresis, and the transcriptional expression of genes related to flagellum movement was detected by RT-qPCR. The effects of wild strain EGDe and CodY deficient strain on the hemolytic activity of bacteria, the half lethal dose of Helicoverpa armigera larvae, the main virulence factor LLO and the transcriptional expression of virulence gene regulatory protein PrfA were compared. Results: compared with wild-type strains, the transcription and expression of flagellum movement and related genes, the main virulence factors LLO and PrfA, and hemolytic activity of CodY-deficient strains were significantly decreased (P < 0. 01), and the hemolytic activity was significantly lower than that of wild-type strains (P < 0. 01). The lethal dose to Helicoverpa armigera larvae increased 5.8 times. Conclusion: CodY plays an important role in flagellum movement and bacterial virulence regulation of Lm.
【作者单位】：华中师范大学生命科学学院遗传调控与整合生物学湖北省重点实验室;
【基金】：国家自然科学基金(31571931) 华中师范大学中央高校基本科研业务费(CCNU15A02026)资助项目
【分类号】：R378

【参考文献】