IS-Mediated Mobilization of the Colistin Resistance Gene in .

Objectives: The emergence of mobile colistin resistance genes has compromised the efficacy of the last resort antibiotic, colistin, in clinical treatment. The gene was first identified in Belgium in association with the insertion sequence IS. However, the molecular mechanisms of mobilization are not well understood.

Methods: To further explore the mobilization of gene via IS, we constructed a conjugative plasmid that carries an intact composite transposon Tn7052. Transposition assays were performed by conjugation, the transposition sites were characterized by arbitrary primed PCR and DNA sequencing.

Results: In this study, we experimentally demonstrated that could be mobilized as a composite transposon Tn7052 and its transposition generated 8-bp AT-rich duplications in the host genome.

Conclusion: These results indicate that gene could be mobilized by IS, the current investigations provide mechanistic insights in the transposition of .