环丙沙星对肠致病性大肠埃希菌转录谱基因表达的影响

发布时间：2018-04-25 21:48

本文选题：肠致病性大肠埃希菌 + 环丙沙星　；参考：《中国病原生物学杂志》2015年02期

【摘要】：目的探讨不同浓度环丙沙星对肠致病性大肠埃希菌转录基因表达的影响。方法在肠致病性大肠埃希菌对数生长期加入不同浓度环丙沙星(高浓度组4μg/ml,低浓度组2μg/ml),对照组加入生理盐水,分别于0、45、90、135和180min时收集菌液,提取细菌总RNA,使用表达谱芯片检测环丙沙星作用后肠致病性大肠埃希菌在转录过程中的基因变化,分析各时间点大肠埃希菌转录水平差异;筛选差异基因,采用荧光定量PCR验证差异基因表达。结果与生理盐水组比较,4μg/ml环丙沙星组大肠埃希菌共有1 724个基因转录上调,1 806个基因转录下调,2μg/ml组中共有988个基因转录上调,2 297个基因转录下调。在表达差异的基因中,以编码假设合成蛋白及转录调控蛋白基因数最多。两组中有共性的基因为21个,这些基因在不同浓度及所有的5个时间点均下调表达,表达的基因包括编码ABC转运膜蛋白基因和菌毛蛋白基因。在2μg/ml与4μg/ml组的对比中,未观察到环丙沙星影响肠致病性大肠埃希菌致病岛毒力基因的表达差异(P0.05)。差异表达的基因通过荧光定量PCR检测均有统计学意义(分别与生理盐水组比较,P0.05)。结论不同浓度环丙沙星体外对肠致病性大肠埃希菌毒力基因转录的影响无显著性差别,但对耐药相关基因转录具有显著影响,这些影响是否与对肠致病性大肠埃希菌对环丙沙星耐药有关仍需进一步研究。
[Abstract]:Objective to investigate the effects of ciprofloxacin (ciprofloxacin) at different concentrations on the expression of transcriptional genes in enteropathogenic Escherichia coli. Methods different concentrations of ciprofloxacin (4 渭 g / ml in high concentration group, 2 渭 g / ml in low concentration group and normal saline in control group) were added to the logarithmic growth phase of Escherichia coli. The bacterial total RNAs were extracted, and the gene changes in the transcriptional process of Escherichia coli after ciprofloxacin treatment were detected by using the expression microarray, and the transcription level of Escherichia coli was analyzed at different time points, and the differentially expressed genes were screened. The differentially expressed genes were verified by fluorescence quantitative PCR. Results compared with saline group, 1 724 genes of Escherichia coli in 4 渭 g/ml ciprofloxacin group were up-regulated and 1 806 genes were down-regulated. In 2 渭 g/ml group, 988 genes were up-regulated and 2 297 genes were down-regulated. Among the differentially expressed genes, the number of genes encoding hypothetical synthetic protein and transcriptional regulatory protein was the highest. There were 21 common genes in the two groups. These genes were down-regulated at different concentrations and at all 5 time points. The expressed genes included the ABC transporter membrane protein gene and the fimbrial protein gene. In the comparison of 2 渭 g/ml and 4 渭 g/ml groups, there was no significant difference in the expression of virulence gene between ciprofloxacin and 4 渭 g/ml in pathogenic Escherichia coli. The differentially expressed genes were detected by fluorescence quantitative PCR. Conclusion the effects of ciprofloxacin at different concentrations on virulence gene transcription of Enteropathogenic Escherichia coli were not significantly different in vitro, but had significant effects on drug resistance related gene transcription. Whether these effects are related to the resistance of Escherichia coli to ciprofloxacin needs further study.
【作者单位】：广东医学院附属深圳市南山区人民医院感染科深圳市内源性感染诊治重点实验室;
【基金】：国家自然科学基金项目(No.81170370/H0312) 深圳市科创委项目(No.JCYJ20130402151227180) 深圳市卫人委项目(No.201203203,201203211,201302199,201303186,201401083,201401084,201402130,201402131,201402133) 深圳市医学重点学科经费资助项目
【分类号】：R96

【参考文献】