Inhibition of Streptococcus mutans biofilms with bacterial-derived outer membrane vesicles

BMC Microbiol. 2021 Aug 24;21(1):234. doi: 10.1186/s12866-021-02296-x.

Abstract

Background: Biofilms are microbial communities surrounded by a self-produced extracellular matrix which protects them from environmental stress. Bacteria within biofilms are 10- to 1000-fold more resistant to antibiotics, making it challenging but imperative to develop new therapeutics that can disperse biofilms and eradicate infection. Gram-negative bacteria produce outer membrane vesicles (OMV) that play critical roles in communication, genetic exchange, cargo delivery, and pathogenesis. We have previously shown that OMVs derived from Burkholderia thailandensis inhibit the growth of drug-sensitive and drug-resistant bacteria and fungi.

Results: Here, we examine the antibiofilm activity of Burkholderia thailandensis OMVs against the oral biofilm-forming pathogen Streptococcus mutans. We demonstrate that OMV treatment reduces biofilm biomass, biofilm integrity, and bacterial cell viability. Both heat-labile and heat-stable components, including 4-hydroxy-3-methyl-2-(2-non-enyl)-quinoline and long-chain rhamnolipid, contribute to the antibiofilm activity of OMVs. When OMVs are co-administered with gentamicin, the efficacy of the antibiotic against S. mutans biofilms is enhanced.

Conclusion: These studies indicate that bacterial-derived OMVs are highly effective biological nanoparticles that can inhibit and potentially eradicate biofilms.

Keywords: Bacteria; Biofilm; Burkholderia; Nanoparticle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Outer Membrane / chemistry
  • Biofilms / drug effects*
  • Biofilms / growth & development*
  • Extracellular Vesicles / chemistry*
  • Gentamicins / pharmacology
  • Microbial Sensitivity Tests
  • Streptococcus mutans / drug effects
  • Streptococcus mutans / pathogenicity
  • Streptococcus mutans / physiology*

Substances

  • Anti-Bacterial Agents
  • Gentamicins