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The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
08:06

The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions

Published on: February 1, 2018

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Plasmids carrying DHA-1 β-lactamases

Claire Hennequin1,2, Viviane Ravet3, Frédéric Robin4,5,6

  • 1Université Clermont Auvergne, CNRS, Laboratoire Microorganismes: Génome et Environnement, Clermont-Ferrand, France. claire.hennequin@uca.fr.

European Journal of Clinical Microbiology & Infectious Diseases : Official Publication of the European Society of Clinical Microbiology
|April 18, 2018
PubMed

Insights

Plasmids carrying the DHA-1 cephalosporinase gene are spreading globally in bacteria like Klebsiella pneumoniae. These plasmids often harbor multiple antibiotic resistance genes, contributing to multidrug resistance.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • The DHA-1 cephalosporinase is a significant beta-lactamase conferring antibiotic resistance.
  • Plasmids mediating DHA-1 cephalosporinase have been identified globally, originating from Salmonella sp. in the 1990s.
  • These resistance determinants are primarily found in Klebsiella pneumoniae but also in other bacterial species.

Purpose of the Study:

  • To provide an updated review of plasmids mediating DHA-1 cephalosporinase.
  • To highlight the global dissemination and characteristics of these resistance plasmids.
  • To detail the genetic makeup and mobility of DHA-1 carrying plasmids.

Main Methods:

  • Literature review of studies reporting DHA-1 cephalosporinase plasmids.
  • Analysis of plasmid characteristics including size, incompatibility groups, and transferability.
  • Examination of the genetic context and co-expressed resistance genes.

Main Results:

  • DHA-1 cephalosporinase plasmids are found worldwide, predominantly in Klebsiella pneumoniae.
  • These plasmids exhibit considerable diversity in size (22-313 kb) and incompatibility groups (e.g., R, L/M, FII(k)).
  • The blaDHA-1 gene is frequently co-expressed with a wide array of other antibiotic resistance genes, forming a mosaic multidrug resistance region.

Conclusions:

  • Plasmids carrying DHA-1 cephalosporinase represent a significant challenge due to their global spread and association with multidrug resistance.
  • The genetic plasticity and mosaic structure of these plasmids facilitate the dissemination of various antibiotic resistance genes.
  • Continued surveillance and characterization of DHA-1 mediating plasmids are crucial for combating antimicrobial resistance.
Keywords:
AmpCAntibiotic resistanceCephalosporinaseDHA-1Klebsiella pneumoniaePlasmids

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