Identification and Characterization of a Novel SXT/R391 Integrative and Conjugative Element in a Food Isolate.

is an opportunistic human pathogen. In this study, a novel SXT/R391 integrative and conjugative element (ICE), named ICEChnS012, was identified in the multidrug-resistant strain S012 that was isolated from retail chicken in China. Whole genome sequencing revealed that ICEPChnS012 carried 22 resistance genes including , , , , and . ICEPChnS012 harbored 10 copies of IS and IS-mediated genetic new rearrangements caused variations in HS4 region. To our knowledge, an unusual gene cassette array was found in in this study for the first time. And this is the first report of identification of and in VRIII region in The conjugation experiments proved that ICEChnS012 could be transferred to EC600 through conjugation. These findings demonstrated that ICEChnS012 was a special ICE that carried the largest number of antimicrobial resistance genes in the family of SXT/R391 ICEs. This element could serve as an important vehicle for the dissemination of antibiotic resistance genes and should receive great concern.