Characterization of Klebsiella pneumoniae carbapenemase (KPC)-14, a KPC variant conferring resistance to ceftazidime-avibactam in the extensively drug-resistant ST463 Pseudomonas aeruginosa clinical isolate

OBJECTIVE: We studied two Klebsiella pneumoniae carbapenemase (KPC)-14 variants from clinical Pseudomonas aeruginosa isolates (C137 and C159) to better understand the genomic diversity, mechanisms, and genes that confer antibiotic resistance and pathogenicity. METHODS: Genomic DNA from C137/159 was subjected to Illumina and Oxford Nanopore sequencing. Horizontal transmission of the plasmid was evaluated using cloning experiments. The expression of efflux pumps, the outer membrane protein OprD, and the enzyme AmpC was quantified using qRT-PCR. The detectability of KPC-14 was evaluated using different methods, and biofilm formation assays and growth curves were assessed. RESULTS: and KPC variants, which are currently disseminating in this region. CONCLUSIONS: gene carried by PCTs was integrated into the chromosome and exhibited stability throughout bacterial inheritance. Our research highlights the need for improved clinical surveillance of KPC-producing P. aeruginosa.