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Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
Published on: January 1, 2016
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Bacteria that inhibit quorum sensing decrease biofilm formation and virulence in Pseudomonas aeruginosa PAO1.
Steven E A Christiaen1, Nele Matthijs, Xiao-Hua Zhang
1Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium.
Pathogens and Disease
|January 14, 2014
Summary
Quorum quenching (QQ) bacteria show potential as biotherapeutics. Certain QQ isolates and their compounds can inhibit Pseudomonas aeruginosa biofilms and reduce virulence factors, offering new strategies against Gram-negative pathogens.
Area of Science:
- Microbiology
- Bacteriology
- Biotechnology
Background:
- Quorum sensing (QS) regulates virulence in many Gram-negative pathogens.
- Quorum quenching (QQ) offers a strategy to disrupt QS-controlled pathogenicity.
- N-acylhomoserine lactones (AHLs) are common QS signal molecules.
Purpose of the Study:
- To evaluate the biotherapeutic potential of isolated quorum quenching (QQ) bacteria.
- To assess the efficacy of QQ bacterial supernatants against Pseudomonas aeruginosa biofilms and virulence.
- To investigate the in vivo impact of QQ bacteria on pathogen-host interactions.
Main Methods:
- Testing bacterial supernatants for inhibitory effects on P. aeruginosa PAO1 biofilm formation.
- Quantifying biofilm biomass and cell viability.
- Assessing the reduction of P. aeruginosa elastase production.
- Utilizing Caenorhabditis elegans as an in vivo model for virulence testing.
Main Results:
- Most isolates exhibited moderate inhibition of biofilm formation.
- A significant portion of isolates reduced P. aeruginosa elastase production in a dose-dependent manner.
- Co-administration of some QQ isolates increased nematode survival against P. aeruginosa and Burkholderia cenocepacia infections.
Conclusions:
- QQ bacteria and their secreted compounds demonstrate potential for attenuating P. aeruginosa virulence.
- These findings suggest a promising biotherapeutic approach against Gram-negative pathogens employing AHL-mediated QS.
- Further research into QQ bacteria could lead to novel anti-virulence strategies.
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