PhD Student

Supervisor: Asst. Prof. Diane McDougald

Project Title: Does environmental grazing select for virulence in Pseudomonas aeruginosa?

Pseudomonas aeruginosa is an opportunistic pathogen that transits between host and environment, where it is subjected to different selection pressures. Environmental P. aeruginosa has evolved many defenses against protozoan grazers like Acanthamoeba castellani. When defense traits coincide with virulence traits, virulence can be enhanced—"coincidental evolution hypothesis". P. aeruginosa T3SS is implicated in both grazing resistance and virulence in humans, providing a possible mechanism for coincidental evolution. To test whether grazing resistance confers pathogenicity, P. aeruginosa will be co-cultured with A. castellani for multiple generations and tested for resistance against macrophages. Mechanisms for grazing resistance will be elucidated using a transcriptomics approach.