發(fā)布時間：2018-05-04 16:14

  本文選題：大腸埃希菌 + 最小抑菌濃度��； 參考：《畜牧獸醫(yī)學(xué)報》2017年09期

【摘要】：筆者擬研究環(huán)丙沙星誘導(dǎo)對大腸埃希菌臨床耐藥菌株Y35、J45主動外排基因acrA、acrB、acrD、acrE、acrF、mdtA及外排調(diào)控基因marA、robA和soxS mRNA水平的影響。采用微量肉湯稀釋法,測定環(huán)丙沙星對Y35、J45不同誘導(dǎo)階段MIC;采用熒光定量PCR檢測方法,對Y35、J45及二者誘導(dǎo)至10、20、30代菌株的主動外排及外排調(diào)控基因mRNA相對轉(zhuǎn)錄量進(jìn)行測定。結(jié)果顯示:經(jīng)過30代誘導(dǎo),環(huán)丙沙星對誘導(dǎo)株MIC均增至原來的2倍,達(dá)到256μg·mL~(-1)。Y35耐藥株誘導(dǎo)至10和30代時,除了mdtA基因外,其他8個基因轉(zhuǎn)錄量介于1.20~96.07,與未誘導(dǎo)株相比差異顯著(P0.05或P0.01),acrD基因轉(zhuǎn)錄量增加最為明顯;至20代時,acrA、acrB、marA與10代誘導(dǎo)株相比,轉(zhuǎn)錄量下降,但高于原代菌株轉(zhuǎn)錄量;acrE、robA和soxS基因轉(zhuǎn)錄量數(shù)值介于1.40~3.81,與未誘導(dǎo)株相比差異顯著(P0.05或P0.01)。J45耐藥株至10代時,acrB、acrF基因轉(zhuǎn)錄量增加,轉(zhuǎn)錄量分別為原代菌株2.76和1.73倍,其他測定基因轉(zhuǎn)錄量下降;至20代時,acrA、acrB、acrE、mdtA基因轉(zhuǎn)錄量增加顯著,分別為原代菌株的15.35、58.89、31.56、36.50倍,差異極顯著(P0.01);至30代時,所有檢測基因的轉(zhuǎn)錄量均大于原代菌株,acrF基因轉(zhuǎn)錄量增加最為明顯,是原代菌株的102.54倍。本研究表明,長期使用環(huán)丙沙星誘導(dǎo),能夠使臨床耐藥株對其MIC值增加,耐藥性增強(qiáng);環(huán)丙沙星誘導(dǎo)能促使臨床耐藥菌株主動外排基因mRNA轉(zhuǎn)錄量增加,更強(qiáng)的耐藥性可能是由主動外排泵介導(dǎo)產(chǎn)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.
【作者單位】： 河南農(nóng)業(yè)大學(xué)牧醫(yī)工程學(xué)院;
【基金】：國家自然科學(xué)基金(U1304328) 河南省科技廳資助項目(132300410113)
【分類號】：S859.7
，

本文編號：1843694