| 摘要: |
| 【目的】构建鼠伤寒沙门菌BaeSR和AcrB双基因缺失株，探究BaeSR和AcrB对鼠伤寒沙门菌耐药性的影响。【方法】采用自杀质粒pLP12介导的同源重组系统构建鼠伤寒沙门菌标准株CR的AcrB基因缺失株CR△AcrB以及AcrB和BaeSR双基因缺失株 CR△BaeSR△AcrB，比较分析鼠伤寒沙门菌缺失株与标准株对氨苄西林、阿莫西林、头孢噻呋、阿米卡星、安普霉素、四环素、强力霉素、阿奇霉素、恩诺沙星、环丙沙星、氟苯尼考、氯霉素12种药物的敏感性及生长特性、生物膜形成能力、运动性等生物学特性差异。【结果】成功构建了鼠伤寒沙门菌标准株CR的基因缺失株CR△AcrB和CR△BaeSR△AcrB。药物敏感性结果显示，与标准株CR相比，CR△AcrB对12种药物的MIC值均有不同程度的降低；与CR△AcrB相比，CR△BaeSR△AcrB对除青霉素类（氨苄西林和阿莫西林）以外的10种药物MIC下降了50%~87.5%。与标准株CR相比，CR△AcrB和CR△BaeSR△AcrB的生长速率无明显变化，但其生物膜形成能力（P＜0.01）及运动性（P＜0.05）均显著下降。【结论】鼠伤寒沙门菌AcrB和BaeSR基因缺失后，细菌的运动性及生物膜形成能力显著下降，对多种抗生素的敏感性增强。 |
| 关键词: 鼠伤寒沙门菌 外排泵AcrB 基因敲除 耐药性 |
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| 基金项目:国家自然科学基金项目（31772802）；安徽高校自然科学重点研究项目（KJ2017A132） |
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| Construction and resistance to antibiotics of AcrB and BaeSR gene knock-out strains of Salmonella typhimurium |
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XU Jun,GAO Haixia,LI Rui,et al
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| Abstract: |
| 【Objective】The BaeSR and AcrB gene deletion strains of Salmonella typhimurium were constructed to study the effect of BaeSR and AcrB on antibiotic resistance of S. typhimurium.【Method】Based on S. typhimurium standard strain CR,deleted mutants CR△AcrB and CR△BaeSR△AcrB were obtained by homologous recombination mediated by suicide plasmid pLP12.The differences in MIC,growth characteristics,biofilm formation ability and motility of the deleted strains and standard strains CR against Ampicillin,Amoxicillin,Ceftiofur,Amikacin,Apramycin,Tetracycline,Doxycycline,Azithromycin,Enrofloxacin,Ciprofloxacin and Flufenicol were compared and analyzed.【Result】This study successfully constructed the gene deletion strains of CR△AcrB and CR△BaeSR△AcrB.The MIC of the twelve antibiotics in gene deletion strains were lower than those in standard strains CR.Compared with CR△AcrB,MIC of CR△BaeSR△AcrB were decreased by 50%-87.5% for 10 drugs except Penicillins (AMP and AMX).The growth rates of CR△AcrB and CR△BaeSR△AcrB did not change significantly compared with CR,but the biofilm formation ability (P<0.01) and motility (P<0.05) decreased significantly.【Conclusion】The deletion of AcrB and BaeSR genes in S. typhimurium significantly decreased the motility of bacteria and the ability of biofilm formation,while increased the sensitivity to various antibiotics. |
| Key words: Salmonella typhimurium AcrB efflux pump gene knock-out antibiotic resistance |
