Methicillin-Resistant Staphylococcus aureus Grown on Vancomycin-Supplemented Screening Agar Displays Enhanced Biofilm Formation

Antimicrob Agents Chemother. 2015 Dec;59(12):7906-10. doi: 10.1128/AAC.00568-15. Epub 2015 Oct 12.

Abstract

Brain heart infusion agar containing 3 mg/liter vancomycin (BHI-V3) was used to screen for heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA). There was markedly greater biofilm formation by isolates that grew on BHI-V3 than by strains that did not grow on BHI-V3. Increased biofilm formation by hVISA may be mediated by FnbA- and polysaccharide intercellular adhesin-dependent pathways, and upregulation of atlA and sarA may also contribute to enhanced biofilm formation by hVISA upon prolonged exposure to vancomycin.

MeSH terms

  • Agar
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Biofilms / drug effects*
  • Biofilms / growth & development
  • Culture Media / chemistry
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial*
  • Humans
  • Methicillin / pharmacology
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Methicillin-Resistant Staphylococcus aureus / genetics*
  • Methicillin-Resistant Staphylococcus aureus / growth & development
  • Methicillin-Resistant Staphylococcus aureus / metabolism
  • Microbial Sensitivity Tests
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism
  • Staphylococcal Infections / microbiology
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Vancomycin / pharmacology
  • Vancomycin Resistance / genetics

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Culture Media
  • RNA, Messenger
  • SarA protein, bacterial
  • Trans-Activators
  • Vancomycin
  • Agar
  • Methicillin