环丙沙星诱导对临床耐药菌株主动外排基因转录的影响

发布时间：2018-05-04 16:14

  本文选题：大肠埃希菌 + 最小抑菌浓度　； 参考：《畜牧兽医学报》2017年09期

【摘要】：笔者拟研究环丙沙星诱导对大肠埃希菌临床耐药菌株Y35、J45主动外排基因acrA、acrB、acrD、acrE、acrF、mdtA及外排调控基因marA、robA和soxS mRNA水平的影响。采用微量肉汤稀释法,测定环丙沙星对Y35、J45不同诱导阶段MIC;采用荧光定量PCR检测方法,对Y35、J45及二者诱导至10、20、30代菌株的主动外排及外排调控基因mRNA相对转录量进行测定。结果显示:经过30代诱导,环丙沙星对诱导株MIC均增至原来的2倍,达到256μg·mL~(-1)。Y35耐药株诱导至10和30代时,除了mdtA基因外,其他8个基因转录量介于1.20~96.07,与未诱导株相比差异显著(P0.05或P0.01),acrD基因转录量增加最为明显;至20代时,acrA、acrB、marA与10代诱导株相比,转录量下降,但高于原代菌株转录量;acrE、robA和soxS基因转录量数值介于1.40~3.81,与未诱导株相比差异显著(P0.05或P0.01)。J45耐药株至10代时,acrB、acrF基因转录量增加,转录量分别为原代菌株2.76和1.73倍,其他测定基因转录量下降;至20代时,acrA、acrB、acrE、mdtA基因转录量增加显著,分别为原代菌株的15.35、58.89、31.56、36.50倍,差异极显著(P0.01);至30代时,所有检测基因的转录量均大于原代菌株,acrF基因转录量增加最为明显,是原代菌株的102.54倍。本研究表明,长期使用环丙沙星诱导,能够使临床耐药株对其MIC值增加,耐药性增强;环丙沙星诱导能促使临床耐药菌株主动外排基因mRNA转录量增加,更强的耐药性可能是由主动外排泵介导产生。
[Abstract]:The effect of ciprofloxacin induction on the active efflux gene acrAgna acrBnacrDnacrDtA acrEacrFFCF-mdtA and the efflux regulatory genes marArobA and soxS mRNA of Escherichia coli strain Y35FJ45 was studied in this paper. The effect of ciprofloxacin on the active efflux gene of Escherichia coli Y35MJ45 was studied. Microbroth dilution method was used to determine the relative transcription of the active efflux gene (mRNA) of ciprofloxacin on Y35OJ45 at different stages of induction, and the fluorescence quantitative PCR method to detect the active efflux and mRNA transcription of the two strains. The results showed that after 30 generations of induction, ciprofloxacin increased to 2 times of the original MIC, reaching 256 渭 g mL~(-1).Y35 resistance to 10 and 30 generations, except for mdtA gene. The transcription quantity of the other 8 genes was between 1.20 and 96.07, which was significantly higher than that of the uninduced strain (P0.05 or P0.01P0.01), and decreased at the 20th generation, compared with that of the 10th generation induced strain, and the expression of the other eight genes was significantly higher than that of the induced strain of the 10th generation (P < 0.05), but the transcription of the other 8 genes was significantly higher than that of the induced strain at the 20th generation. However, the transcriptional quantity of soxS gene was between 1.40 and 3.81, which was significantly higher than that of the original strain (P 0.05 or P0.01).J45 resistant strain) at the 10th generation, and the transcription quantity was 2.76 and 1.73 times higher than that of the original strain, respectively. By the 20th generation, the transcriptional amount of the gene was increased significantly, which was 36.50 times as much as that of the original strain (15.35 ~ 58.89), and the difference was extremely significant (P 0.01), and the difference was significant (P < 0.05) at the end of the 20th generation, and the difference was significant (P < 0.05), the difference was significant (P < 0.05), and the difference was significant (P < 0.05). The transcriptional amount of all the detected genes was 102.54 times higher than that of the original strain. The results showed that long-term ciprofloxacin induction could increase the MIC value and drug resistance of clinical resistant strains, and induce ciprofloxacin to induce the increase of mRNA transcription of active efflux gene in clinical resistant strains. Stronger drug resistance may be mediated by active efflux pumps.
【作者单位】： 河南农业大学牧医工程学院;
【基金】：国家自然科学基金(U1304328) 河南省科技厅资助项目(132300410113)
【分类号】：S859.7
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本文编号：1843694