A novel KPC-113 variant conferring carbapenem and ceftazidime-avibactam resistance in a multidrug-resistant Pseudomonas aeruginosa isolate

This study aimed to characterize a novel KPC-113 variant from a clinical Pseudomonas aeruginosa isolate R20-14.Genomic DNA of R20-14 was subjected to Illumina and Oxford Nanopore sequencing. The horizontal transmission of plasmid was evaluated with conjugation experiments. Minimum inhibitory concentrations of bacterial strains were obtained using broth microdilution methods. KPC-113 detectability of different carbapenemase detection methods was tested. The kinetic parameters of KPC-113 were compared with those of KPC-2 by a spectrophotometer. Structure modelling and molecular docking of KPC-2 and KPC-113 were performed using Schrödinger.R20-14, a sequence type 3903 multidrug-resistant strain, was resistant to carbapenems and ceftazidime-avibactam (CZA) concurrently. S1-nuclease pulsed-field gel electrophoresis and genomic analysis revealed a blaKPC-113 is a novel KPC variant mediating both CZA resistance and carbapenem resistance. It is of great concern that bla