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Carbapenem Resistance Caused by High-Level Expression of OXA-663 ?-Lactamase in an OmpK36-Deficient Klebsiella pneumoniae Clinical Isolate.

ABSTRACT: Carbapenem resistance is mainly mediated by carbapenemases or extended-spectrum ?-lactamases (ESBL) plus a loss of porins. However, we have identified a Klebsiella pneumoniae clinical isolate that contains neither carbapenemases nor ESBLs. Instead, we found that high-level expression of a novel bla OXA-10-derived ?-lactamase gene, bla OXA-663, in conjunction with OmpK36 deficiency results in high-level carbapenem resistance. This finding demonstrates the combinatorial complexity of factors, including ?-lactamase activity, its expression levels, and porin activity, that yield carbapenem resistance.

SUBMITTER: Ma P

PROVIDER: S-EPMC6201135 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Carbapenem Resistance Caused by High-Level Expression of OXA-663 β-Lactamase in an OmpK36-Deficient Klebsiella pneumoniae Clinical Isolate.

Ma Peijun P Laibinis Hannah H HH Ernst Christoph M CM Hung Deborah T DT

Antimicrobial agents and chemotherapy 20181024 11

Carbapenem resistance is mainly mediated by carbapenemases or extended-spectrum β-lactamases (ESBL) plus a loss of porins. However, we have identified a Klebsiella pneumoniae clinical isolate that contains neither carbapenemases nor ESBLs. Instead, we found that high-level expression of a novel blaOXA-10-derived β-lactamase gene, blaOXA-663, in conjunction with OmpK36 deficiency results in high-level carbapenem resistance. This finding demonstrates the ...[more]

PMID: 30126962

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