Characterization of the Genetic Background of KPC-2-Producing Klebsiella pneumoniae with Insertion Elements Disrupting the ompK36 Porin Gene

Microb Drug Resist. 2020 Sep;26(9):1050-1057. doi: 10.1089/mdr.2019.0410. Epub 2020 Apr 13.

Abstract

Carbapenemase-producing combined porin loss is one of the primary mechanisms for carbapenem resistance. Although mutations in ompK35 and ompK36 genes have often been identified in carbapenem-resistant Klebsiella pneumoniae, reports on the porin protein gene disruption by insertion sequence (IS) elements are varied. The ompK36 porin protein gene disruption by IS elements and OmpK36 production loss in six blaKPC-2-carrying K. pneumoniae isolates were detected in this study. IS903, ISEc68, and IS1 insertions were noted in the 3, 2, and 1 isolates, respectively. The six K. pneumoniae isolates showed five different pulsed-field gel electrophoresis patterns and belonged to four multilocus sequence typing types, ST4, ST11, ST15, and ST39. This study increases our understanding of the genetic background of KPC-2 carbapenemases in porin-defective clinical isolates and the contribution of OmpK36 production loss to carbapenem resistance.

Keywords: KPC-2; Klebsiella pneumoniae; OmpK36; carbapenemase; insertion sequence.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Carbapenems / pharmacology
  • Electrophoresis, Gel, Pulsed-Field
  • Humans
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / classification
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / genetics*
  • Klebsiella pneumoniae / isolation & purification
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Mutagenesis, Insertional*
  • Phylogeny
  • Porins / deficiency
  • Porins / genetics*
  • beta-Lactam Resistance / genetics*
  • beta-Lactamases / genetics*
  • beta-Lactamases / metabolism

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • OmpK36 protein, Klebsiella pneumoniae
  • Porins
  • beta-Lactamases
  • beta-lactamase KPC-2, Klebsiella pneumoniae