The VirAB-VirSR-AnrAB multi-component system involves in resistance of EGD-e to cephalosporins, bacitracin, nisin, benzalkonium chloride and ethidium bromide.

Author(s) Jiang, X.; Geng, Y.; Ren, S.; Yu, T.; Li, Y.; Liu, G.; Wang, H.; Meng, H.; Shi, L.
Journal Appl Environ Microbiol
Date Published 2019 Aug 09
Abstract

In , it has been proposed that the VirSR TCS and two ABC transporters VirAB and AnrAB constitute a complex TCS/ABC transporter system which has been recognized as a unique resistance mode. The role of the putative VirAB-VirSR-AnrAB system in antimicrobial resistance and the respective contribution of each member to resistance were investigated in this study. We constructed the gene deletion mutants of EGD-e and the complemented strains of the mutants, and determined minimum inhibitory concentrations (MICs) of these strains against antimicrobial agents using the agar dilution method. We assessed the relative expression levels of target genes by RT-qPCR and measured the promoter activity by β-galactosidase assays. Our results showed that the VirAB-VirSR-AnrAB system mediates not only nisin and bacitracin resistance, but also cephalosporins, ethidium bromide (EtBr) and benzalkonium chloride (BC) resistance. In this system, two ABC transporters VirAB and AnrAB play distinct roles in cefotaxime resistance: the former is only responsible for antimicrobial sensing and signalling by VirSR, while the latter contributes to transport antimicrobial. Notably, VirAB itself, instead of the VirAB-VirSR-AnrAB system, contributes to kanamycin and tetracycline resistance. Based on the results obtained from this study, we speculate that VirAB acts as a sensor for VirSR in response to cephalosporins, bacitracin, nisin, EtBr and BC, while VirAB itself plays a role in response to kanamycin and tetracycline EGD-e.This study describes TCS/ABC transporter modules characterized in EGD-e. It consists of the VirSR TCS and the VirAB and AnrAB ABC transporters. Our results showed that this system is involved in nisin and bacitracin resistance, as well as cephalosporins, ethidium bromide (EtBr) and benzalkonium chloride (BC) resistance. In this system, VirAB is only responsible for antimicrobial sensing and signalling by VirSR, while AnrAB contributes to transport antimicrobial. Interestingly, VirAB itself, instead of the VirAB-VirSR-AnrAB system, contributes to kanamycin and tetracycline resistance.

DOI 10.1128/AEM.01470-19
ISSN 1098-5336
Citation Jiang X, Geng Y, Ren S, Yu T, Li Y, Liu G, et al. The VirAB-VirSR-AnrAB multi-component system involves in resistance of EGD-e to cephalosporins, bacitracin, nisin, benzalkonium chloride and ethidium bromide. Appl Environ Microbiol. 2019.

Related Applications, Forms & Industries