Resistance to cationic surfactants and some other agents of Escherichia coil recombinants with an abundant number of genes encoding drug efflux pump

Abstract

In order to investigate the contribution of the multidrug efflux pumps to cellular resistance to a variety of agents including cationic surfactants, we cloned genes of major drug efflux pumps of Escherichia coil and transformed strain JM109 with plasmids encoding those genes. In emrAB-, mdfA- and emrE-recombinants, the resistance to carbonylcyanide-m-chlorophenylhydrazone (CCCP), chloramphenicol, and paraquat, respectively, was increased compared to their parent bearing pUC18. Also, in mdfA- and emrE-recombinants, the resistance to cetyltrimethylammonium bromide (CTAB) was increased. However, no significant effects of abundant numbers of emrD and envCD could be observed on resistance to agents examined.