Roles of Efflux Pumps from Different Superfamilies in the Surface-Associated Motility and Virulence of ATCC 17978.

Although the relationship between efflux pumps and antimicrobial resistance is well documented, less is known about the involvement of these proteins in the pathogenicity of this nosocomial pathogen. In previous work, we identified the AbaQ major facilitator superfamily (MFS) efflux pump and demonstrated its participation in the motility and virulence of In the present study, we examined the role in these processes of transporters belonging to different superfamilies of efflux pumps. Genes encoding known or putative permeases belonging to efflux pump superfamilies other than the MFS were selected, and the corresponding knockouts were constructed. The antimicrobial susceptibilities of these mutants were consistent with previously reported data. In mutants of strain ATCC 17978 carrying inactivated genes encoding the efflux pumps (resistance nodulation division [RND]), (multidrug and toxic compound extrusion [MATE]), and (small multidrug resistance [SMR]), as well as the newly described ATP-binding cassette (ABC) permeases and , both surface-associated motility and virulence were reduced compared to the parental strain. However, inactivation of the genes encoding the known ABC permeases and , the newly identified putative ABC permeases 0027 and , or the roteobacterial ntimicrobial ompound fflux (PACE) transporters and had no effects on bacterial motility or virulence. Our results demonstrate the involvement of antimicrobial transporters belonging at least to five of the six known efflux pump superfamilies in both surface-associated motility and virulence in ATCC 17978.