Analysis of borderline-resistant strains of methicillin-resistant Staphylococcus aureus using polymerase chain reaction

Microbiol Immunol. 1992;36(5):445-53. doi: 10.1111/j.1348-0421.1992.tb02043.x.


Identification of methicillin-resistant Staphylococcus aureus by drug-susceptibility tests alone poses a serious problem, because a considerable number of clinical S. aureus isolates are borderline resistant to methicillin. To circumvent this problem, we have developed a quick and sensitive method of PCR amplification for the detection of mecA gene, which, coding for PBP2', is the specific genetic element of methicillin-resistant Staphylococcus aureus. This method made it possible to identify MRSA strains in a short time using as few as 30 cells as a starting material for template DNA. Using this method, we found that the strains of borderline methicillin-resistance could be accurately identified. We also found one S. aureus clinical strain, T3, which lacked mecA gene in spite of its resistance to methicillin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA, Bacterial / analysis
  • Genes, Bacterial
  • Immunoblotting
  • Methicillin Resistance*
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Oligonucleotides
  • Polymerase Chain Reaction*
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / isolation & purification*


  • DNA, Bacterial
  • Oligonucleotides