The Integrative and Conjugative Element ICEPOL2 Contributes to the Outbreak of Multi-Antibiotic-Resistant Bacteria for Spp. and Spp.

Antibiotic resistance genes (ARGs) and horizontal transfer of ARGs among bacterial species in the environment can have serious clinical implications as such transfers can lead to disease outbreaks from multidrug-resistant (MDR) bacteria. Infections due to antibiotic-resistant and in intensive care units have been increasing in recent years. In this study, the multi-antibiotic-resistant strain sp. POL2 was isolated from the wastewater of a livestock farm. Whole-genome sequencing and annotation revealed that the POL2 genome encodes dozens of ARGs. The integrative and conjugative element (ICE) ICEPOL2, which encodes ARGs associated with four types of antibiotics, including carbapenem, was identified in the POL2 genome, and phylogenetic affiliation analysis suggested that ICEPOL2 evolved from related ICEs of spp. Conjugation assays verified that ICEPOL2 can horizontally transfer to species, suggesting that ICEPOL2 contributes to the dissemination of multiple ARGs among spp. and spp. Because spp. is associated with clinically significant infections and high mortality, there would be challenges to clinical treatment if these bacteria acquire ICEPOL2 with its multiple ARGs, especially the carbapenem resistance gene. Therefore, the results of this study support the need for monitoring the dissemination of this type of ICE in and strains to prevent further outbreaks of MDR bacteria. Infections with multiple antibiotic-resistant and in intensive care units have been increasing in recent years. In this study, the mobile integrative and conjugative element ICEPOL2, which was associated with the transmission of a carbapenem resistance gene, was identified in the genome of the multi-antibiotic-resistant strain sp. POL2. ICEPOL2 is closely related to the ICEs from species, and ICEPOL2 can horizontally transfer to species with the gene as the insertion site. Because species are associated with clinically significant infections and high mortality, the ability of ICEPOL2 to transfer carbapenem resistance from environmental strains of to is of clinical concern.