p1220-CTXM, a pKP048-related IncFIIK plasmid carrying bla CTX-M-14 and qnrB4

AIM: This study aimed to characterize plasmid-mediated antimicrobial resistance in clinical Klebsiella pneumoniae 1220 carrying bla CTX-M-14 and qnrB4. MATERIALS & METHODS: Plasmid p1220-CTXM was transformed from the 1220 isolate into Escherichia coli through conjugal transfer and then fully sequenced. Antimicrobial susceptibility was determined by VITEK. RESULTS: p1220-CTXM was an IncFIIK plasmid genetically closely related to pKP048 and carried resistance markers including bla CTX-M-14, bla DHA-1, qnrB4, sul1 and qacEΔ1, all of which were harbored in a 35.7-kb multidrug-resistant region. bla CTX-M-14 was located in a truncated ISEcp1-bla CTX-M-14-orf477 transposition unit, and qnrB4 and bla DHA-1 were in a truncated qnrB4-bla DHA-1 region. CONCLUSION: This study provided the insight into the co-occurrence of bla CTX-M-14 and qnrB4 and the evolution of pKP048-related IncFIIK plasmids.