Novel plasmid-borne multidrug resistance gene cluster including lsa(E) from a linezolid-resistant Enterococcus faecium of swine origin

A novel non-conjugative plasmid of 28,489 bp from a porcine linezolid-resistant Enterococcus faecium isolate was completely sequenced. This plasmid harbored a novel type of multiresistance gene cluster that comprised the resistance genes lnu(B), lsa(E), spw, aadE, aphA3 and two copies of erm(B), which account for resistance to macrolides, lincosamides, streptogramins, pleuromutilins, streptomycin, spectinomycin and kanamycin/neomycin. Structural comparisons suggested that this plasmid might have developed from other enterococcal plasmids by IS element-mediated interplasmid recombination processes.