Co-harboring of Novel Plasmid and Integrative and Conjugative Element Carrying Tn in Multidrug-Resistant .

Many strains of the opportunistic pathogen have acquired resistance to multiple antibiotics. Carbapenem-resistant poses a global healthcare problem due to limited therapeutic options for the treatment of infections. Plasmids and integrative and conjugative elements (ICEs) are the major vectors of antibiotic-resistance gene transfer. In our study, four carbapenem-resistant strains of were isolated from the same patient in a tertiary referral hospital in China, one of these was resistant to gentamicin and tobramycin. In this strain P33, we observed a non-transferable plasmid, pP33-2, carrying a novel gene segment (IS- -IS--ORF--IS), which we concluded to have been formed by IS-mediated gene cluster translocation. In addition, by comparing the chromosomes of the strains that belong to the same sequence type, we identified an ICE, ICEP33, adjacent to a prophage. The L site of ICEP33 is identical to the terminal part of the R site of the prophage. The ICEP33 element contains the transposon Tn, which encodes antibiotic and metal resistance genes. The insertion of ICEP33 in the chromosome mediates resistance to multiple antibiotics. Our study contributes to the understanding of the acquisition of antibiotic resistance in facilitated by mobile genetic elements.