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Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
Published on: January 1, 2016
Quorum-sensing and cheating in bacterial biofilms.
Roman Popat1, Shanika A Crusz, Marco Messina
1School of Molecular Medical Sciences, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK. steve.diggle@nottingham.ac.uk
Proceedings. Biological Sciences
|October 5, 2012
Summary
Self-interest in Pseudomonas aeruginosa biofilms can break down cooperation, leading to reduced growth and increased antibiotic susceptibility. Enhancing cooperation mitigates these negative effects of cheating bacteria.
Area of Science:
- Microbiology
- Evolutionary Biology
- Biofilm Dynamics
Background:
- The public goods dilemma describes how self-interest can undermine group cooperation.
- Pseudomonas aeruginosa, an opportunistic pathogen, provides a model to study cooperation in bacterial communities.
Purpose of the Study:
- To investigate the impact of non-cooperative 'cheats' on Pseudomonas aeruginosa biofilm formation and function.
- To understand how quorum-sensing (QS) cheating affects bacterial population fitness and antibiotic resistance.
Main Methods:
- Examined the behavior of Pseudomonas aeruginosa in biofilm populations with and without QS cheats.
- Quantified biofilm thickness, density, population growth, and antibiotic susceptibility.
- Assessed the effect of increasing cooperation levels on population productivity.
Main Results:
- QS cheating was observed in biofilms, exploiting QS-regulated public goods.
- Biofilm thickness, density, and population growth were reduced by cheats, with greater impact in biofilms than planktonic cultures.
- Biofilm susceptibility to antibiotics increased in the presence of cheats.
- Increased cooperation among bacterial cells reduced the negative impact of cheats on productivity.
Conclusions:
- Conflict over public goods significantly reduces bacterial biofilm fitness, more so than in planktonic populations.
- The presence of cheats in biofilms has critical implications for antibiotic treatment strategies.
- Understanding bacterial cooperation and cheating is crucial for managing infections caused by Pseudomonas aeruginosa.
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