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 delta acrABX2 and delta tolCX2 were produced.
Results: Results of E-test to two mutation strains and their parent strain showed that delta acrABX2 and delta tolCX2 were resistant to vancomycin and susceptible to amikacin and cephalothin, which 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: multiple antimicrobial resistance in Salmonella typhimurium. It suggested that the AcrAB-TolC system mediated the multiple antimicrobial resistance in Salmonella typhimurium.