Fusidic acid resistance, mediated by fusB, in bovine coagulase-negative staphylococci

J Antimicrob Chemother. 2006 Dec;58(6):1254-6. doi: 10.1093/jac/dkl418. Epub 2006 Oct 23.


Objectives: The aim of this study was to determine the occurrence of fusidic acid resistance, mediated by the fusB gene, among coagulase-negative staphylococci (CoNS) isolated from bovine mastitis.

Methods: A total of 113 CoNS isolates were screened for susceptibility to fusidic acid by using a disc diffusion method. The fusB gene was detected by using PCR and subsequent DNA sequencing. The localization of fusB was determined by hybridization.

Results: The fusB gene was detected in 3 of 11 fusidic acid-resistant bovine CoNS isolates. The organization of the fusB downstream region on a 40 kb plasmid in a Staphylococcus haemolyticus isolate (288/96) was highly similar to the previously reported organization of fusB on plasmid pUB101 from a Staphylococcus aureus isolate of human origin. The fusB gene was chromosomally located in the remaining two isolates.

Conclusions: Fusidic acid resistance mediated by fusB is not the dominant resistance mechanism in fusidic acid-resistant CoNS studied in this work. The similarity between the organization of the fusB downstream region in S. haemolyticus (isolate 288/96) and on plasmid pUB101 from an S. aureus isolate of human origin indicates a common ancestral origin of these genes.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics*
  • Cattle
  • Chromosomes, Bacterial / genetics
  • Coagulase / analysis
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Drug Resistance, Bacterial / genetics*
  • Evolution, Molecular
  • Fusidic Acid / pharmacology*
  • Genes, Bacterial
  • Genome, Bacterial
  • Mastitis, Bovine / microbiology*
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Nucleic Acid Hybridization
  • Plasmids / genetics
  • Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Staphylococcal Infections / microbiology
  • Staphylococcal Infections / veterinary*
  • Staphylococcus / drug effects*
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / genetics


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Coagulase
  • DNA, Bacterial
  • FusB protein, Staphylococcus aureus
  • Fusidic Acid

Associated data

  • GENBANK/AJ302698