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Published on: March 24, 2023
p1220-CTXM, a pKP048-related IncFIIK plasmid carrying bla CTX-M-14 and qnrB4
Defu Zhang1,2, Zhe Yin1, Yuzong Zhao2
1State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China.
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.
Insights
This study characterized antimicrobial resistance in Klebsiella pneumoniae, detailing the blaCTX-M-14 and qnrB4 genes on the p1220-CTXM plasmid. This provides insight into multidrug resistance evolution in IncFIIK plasmids.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Antimicrobial resistance in Klebsiella pneumoniae is a growing global health concern.
- Plasmids play a crucial role in the dissemination of antibiotic resistance genes.
Purpose of the Study:
- To characterize the plasmid-mediated antimicrobial resistance mechanisms in a clinical isolate of Klebsiella pneumoniae (1220).
- To investigate the genetic elements and evolution of the IncFIIK plasmid carrying blaCTX-M-14 and qnrB4.
Main Methods:
- Conjugal transfer of plasmid p1220-CTXM into Escherichia coli.
- Whole-genome sequencing of the plasmid.
- Antimicrobial susceptibility testing using VITEK system.
Main Results:
- The IncFIIK plasmid p1220-CTXM was successfully transferred and sequenced.
- The plasmid harbored multiple resistance genes, including blaCTX-M-14, blaDHA-1, qnrB4, sul1, and qacEΔ1 within a 35.7-kb multidrug-resistant region.
- Specific genetic structures, such as truncated ISEcp1-blaCTX-M-14-orf477 and qnrB4-blaDHA-1 regions, were identified.
Conclusions:
- The study elucidates the co-occurrence and genetic context of blaCTX-M-14 and qnrB4 on an IncFIIK plasmid.
- Findings contribute to understanding the evolution of pKP048-related IncFIIK plasmids and the spread of antimicrobial resistance.
