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Bacteriophage-mediated competition in Bordetella bacteria
Jaewook Joo1, Michelle Gunny, Marisa Cases
1Department of Veterinary & Biomedical Sciences, Pennsylvania State University, University Park, 16802, USA. jjoo@phys.psu.edu
Proceedings. Biological Sciences
|June 23, 2006
Summary
Bacteriophages (phages) can drive competition between bacterial species. This study shows that a phage
Area of Science:
- * Ecology and microbial interactions
- * Evolutionary biology
- * Mathematical modeling in biology
Background:
- * Apparent competition is a key factor structuring ecological communities, but its mechanisms are not fully understood.
- * Phages, viruses that infect bacteria, can influence bacterial population dynamics and competition.
- * Previous studies have not fully isolated phage-mediated competition from other ecological factors like resource competition.
Purpose of the Study:
- * To isolate and quantify phage-mediated competition between bacterial strains.
- * To develop and test a mathematical model for phage-driven bacterial competition.
- * To determine the key factors influencing the competitive advantage conferred by a lysogenic phage.
Main Methods:
- * Established a model system using two genetically identical *Bordetella* strains, one lysogenic (carrying a phage) and one sensitive to the phage.
- * Neutralized resource competition by using a large excess of nutrients.
- * Quantified the competitive advantage of the lysogenic strain in invasion and resistance using experimental measurements and mathematical modeling.
Main Results:
- * The lysogenic bacterial strain exhibited a competitive advantage over the sensitive strain.
- * This competitive advantage was experimentally quantified and modeled mathematically.
- * The phage's pathology on the sensitive strain was identified as the sole determinant of the competitive advantage, independent of other phage/host parameters.
Conclusions:
- * Phage-mediated interactions significantly impact bacterial community structure.
- * The competitive advantage conferred by a lysogenic phage is primarily determined by its virulence (pathology) against susceptible hosts.
- * This research provides a framework for understanding pathogen/parasite effects on interspecific competition, combining experimental and mathematical approaches.
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