Cfr-mediated linezolid-resistance among methicillin-resistant coagulase-negative staphylococci from infections of humans

PLoS One. 2013;8(2):e57096. doi: 10.1371/journal.pone.0057096. Epub 2013 Feb 20.

Abstract

Four methicillin-resistant coagulase-negative staphylococci (MRCoNS), one Staphylococcus haemolyticus and three Staphylococcus cohnii, from infections of humans collected via the Ministry of Health National Antimicrobial Resistance Surveillance Net (Mohnarin) program in China were identified as linezolid-resistant. These four isolates were negative for the 23S rRNA mutations, but positive for the gene cfr. Mutations in the gene for the ribosomal protein L3, which resulted in the amino acid exchanges Gly152Asp and Tyr158Phe, were identified in S. haemolyticus 09D279 and S. cohnii NDM113, respectively. In each isolate, the cfr gene was located on a plasmid of ca. 35.4 kb, as shown by S1 nuclease pulsed-field gel electrophoresis and Southern blotting experiments. This plasmid was indistinguishable from the previously described plasmid pSS-02 by its size, restriction pattern, and a sequenced 14-kb cfr-carrying segment. Plasmid pSS-02 was originally identified in staphylococci isolated from pigs. This is the first time that a cfr-carrying plasmid has been detected in MRCoNS obtained from intensive care patients in China. Based on the similarities to the cfr-carrying plasmid pSS-02 from porcine coagulase-negative staphylococci, a transmission of this cfr-carrying plasmid between staphylococci from pigs and humans appears to be likely.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetamides / pharmacology
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Coagulase / deficiency*
  • Drug Resistance, Multiple, Bacterial / genetics*
  • Gene Order
  • Humans
  • Linezolid
  • Methicillin Resistance / genetics
  • Microbial Sensitivity Tests
  • Molecular Typing
  • Mutation
  • Oxazolidinones / pharmacology
  • Plasmids / genetics
  • Ribosomal Protein L3
  • Staphylococcal Infections / microbiology
  • Staphylococcus / drug effects
  • Staphylococcus / genetics*
  • Staphylococcus haemolyticus / drug effects
  • Staphylococcus haemolyticus / genetics

Substances

  • Acetamides
  • Bacterial Proteins
  • Coagulase
  • Oxazolidinones
  • RPL3 protein, human
  • Ribosomal Protein L3
  • Linezolid

Grants and funding

This work was supported by grants from the National Science and Technology Major Project (No.2012ZX09303005-003) and National Natural Science Foundation of China (No.31001087). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.