Origin and evolution of DNA associated with resistance to methicillin in staphylococci

Trends Microbiol. 1994 Oct;2(10):343-7. doi: 10.1016/0966-842x(94)90608-4.


The gene mediating resistance to methicillin in staphylococci (mecA) and its flanking sequences (mec DNA) make up a chromosomal DNA locus that is unique to methicillin-resistant bacteria; no equivalent locus exists in methicillin-susceptible cells. The origin of mec DNA is not known, but evidence supports horizontal transfer of mec DNA between different staphylococcal species and of the mecA gene between different Gram-positive genera.

Publication types

  • Review

MeSH terms

  • Chromosome Mapping
  • Cloning, Molecular
  • DNA, Bacterial / genetics*
  • Gene Deletion
  • Genes, Bacterial / genetics
  • Methicillin Resistance / genetics*
  • Sequence Homology, Amino Acid
  • Staphylococcus / genetics*


  • DNA, Bacterial