Phenotypic and Genomic Characterization of AmpC-Producing Klebsiella pneumoniae From Korea

Ann Lab Med. 2018 Jul;38(4):367-370. doi: 10.3343/alm.2018.38.4.367.

Abstract

The prevalence of multidrug-resistant gram-negative bacteria has continuously increased over the past few years; bacterial strains producing AmpC β-lactamases and/or extended-spectrum β-lactamases (ESBLs) are of particular concern. We combined high-resolution whole genome sequencing and phenotypic data to elucidate the mechanisms of resistance to cephamycin and β-lactamase in Korean Klebsiella pneumoniae strains, in which no AmpC-encoding genes were detected by PCR. We identified several genes that alone or in combination can potentially explain the resistance phenotype. We showed that different mechanisms could explain the resistance phenotype, emphasizing the limitations of the PCR and the importance of distinguishing closely-related gene variants.

Keywords: AmpC; Antibiotic resistance; Klebsiella pneumoniae; Korea; Whole Genome Sequencing.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • DNA, Bacterial / isolation & purification
  • DNA, Bacterial / metabolism
  • Drug Resistance, Multiple, Bacterial / genetics
  • Humans
  • Klebsiella Infections / diagnosis*
  • Klebsiella Infections / epidemiology
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / enzymology*
  • Klebsiella pneumoniae / isolation & purification
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Phenotype
  • Polymerase Chain Reaction
  • Republic of Korea / epidemiology
  • Whole Genome Sequencing
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • DNA, Bacterial
  • AmpC beta-lactamases
  • beta-Lactamases