AcrAB-TolC电泵系统介导的鼠伤寒沙门菌多重耐药机理研究

Mechanism of AcrAB-TolC system mediated multiple antimicrobial resistance in Salmonella typhimurium

目的探讨AcrAB-TolC电泵系统在鼠伤寒沙门菌产生多重耐药中的作用。方法利用基因敲除技术,敲除多重耐药鼠伤寒沙门菌野生株X2的acrAB基因和tolC基因,获得两个突变株△tolCX2和△acrABX2。通过基因敲除前后细菌耐药水平的改变,验证AcrAB-TolC系统在鼠伤寒沙门菌产生多重耐药中的作用。结果△tolCX2和△acrABX2对万古霉素耐药,对丁胺卡那霉素、头孢曲松敏感,与野生株X2一致;但对11种抗生素由耐药变为敏感。结论AcrAB-TolC系统与鼠伤寒沙门菌多重耐药的产生有关。

Objective To confirm AcrAB-TolC system mediated the multiple antimicrobial resistance in Salmonella typhimurium. Methods One-step knock-out of chromosomal method was used to disrupt chromosomal genes, in Salmonella typhimurium wild strain X2. The acrAB gene and tolC gene were knocked out and two mutants of the △ acrABX2 and △ tolCX2 were produced. Results Results of E-test to two mutation strains and their parent strain showed that △ acrABX2 and △ tolCX2 were resistant to vancomycin and susceptible to amikacin and cephalothin, which was was similar to their parents isolate X2,but （acrABX2 and （tolCX2 were susceptible to other eleven antimicrobial agents, while the parents isolate X2 was resistant to those. Conclusion It suggested that the AerAB-TolC system mediated the multiple antimierobial resistance in Salmonella typhimurium.