Characterization of KPC-82, a KPC-2 variant conferring resistance to ceftazidime-avibactam in a carbapenem non-susceptible, clinical isolate of Citrobacter koseri

Antimicrob Agents Chemother. 2021 May 10:AAC.00150-21. doi: 10.1128/AAC.00150-21. Online ahead of print.


KPC-82 is a KPC-2 variant, identified in a carbapenem non-susceptible Citrobacter koseri that confers high-level resistance to ceftazidime-avibactam. Genomic analysis revealed that bla KPC-82 is carried by a chromosomally integrated Tn4401 transposon (disrupting porin gene phoE) and evolved by a 6-nucleotide tandem-repeat duplication causing a two-amino-acid insertion (Ser-Asp) within the Ala267-Ser275 loop. Similar to related KPC variants, KPC-82 showed decreased carbapenemase activity when expressed in a heterologous background and remained susceptible to carbapenem/β-lactamase inhibitor combinations.

PMID:33972237 | DOI:10.1128/AAC.00150-21