Molecular Characterization of a Novel Integrative Conjugative Element ICE in .

ICE was identified in the genome of a serovar 8 ST288 isolate YHP170504 from a case of swine lower respiratory tract infection. The aim of the present study was to characterize the integrative conjugative element ICE and its multiresistance region. Susceptibility testing was determined by broth microdilution and the complete ICE was identified by WGS analysis. The full sequence of ICE was analyzed with bioinformatic tools. The presence of ICE, its circular intermediate and integration site were confirmed by PCR and sequence analysis. Transfer of ICE was confirmed by conjugation. ICE has a size of 68,922 bp with 37.42% GC content and harbors 81 genes responsible for replication and stabilization, transfer, integration, and accessory functions, as well as seven different resistance genes [ , (B), , , , , and ]. Conjugation experiments showed that ICE could be transferred to V43 with frequencies of 6.1 × 10. This is the first time a multidrug-resistance ICE has been reported in . Seven different resistance genes were located on a novel integrative conjugative element ICE, which suggests that the ICE is capable of acquiring foreign genes and serving as a carrier for various resistance genes.