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KPC-53, a KPC-3 Variant of Clinical Origin Associated with Reduced Susceptibility to Ceftazidime-Avibactam.

ABSTRACT: This study reports on the characterization of a Klebsiella pneumoniae clinical isolate showing high-level resistance to ceftazidime-avibactam associated with the production of KPC-53, a KPC-3 variant exhibiting a Leu167Glu168 duplication in the Ω-loop and a loss of carbapenemase activity. Whole-genome sequencing (WGS) revealed the presence of two copies of bla _KPC-53, located on a pKpQIL-like plasmid and on a plasmid prophage of the Siphoviridae family, respectively. The present findings provide new insights into the mechanisms of resistance to ceftazidime-avibactam.

SUBMITTER: Di Pilato V

PROVIDER: S-EPMC7927837 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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KPC-53, a KPC-3 Variant of Clinical Origin Associated with Reduced Susceptibility to Ceftazidime-Avibactam.

Di Pilato Vincenzo V Aiezza Noemi N Viaggi Valentina V Antonelli Alberto A Principe Luigi L Giani Tommaso T Luzzaro Francesco F Rossolini Gian Maria GM

Antimicrobial agents and chemotherapy 20201216 1

This study reports on the characterization of a Klebsiella pneumoniae clinical isolate showing high-level resistance to ceftazidime-avibactam associated with the production of KPC-53, a KPC-3 variant exhibiting a Leu167Glu168 duplication in the Ω-loop and a loss of carbapenemase activity. Whole-genome sequencing (WGS) revealed the presence of two copies of blaKPC-53, located on a pKpQIL-like plasmid and on a plasmid prophage of the Siphoviridae family, respectivel ...[more]

PMID: 33106265

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