The ability of the strain Pseudomonas aeruginosa PA14, a clinical isolate from a thermally injured patient, to infect plants allowed for high throughput screenings of bacterial mutants attenuated in virulence in more than one host. The mutants first selected in lettuce and Arabidopsis thaliana were further tested in the mouse model, revealing several bacterial genes that are required for pathogenicity in both plants and mammals.

Besides studying the pathogenicity genes, our group is also interested in studying the hosts' responses against infection and to identify key pathways shared between plants and mammals. For these studies, Arabidopsis is the plant model of choice, since its complete genome is known and DNA microarrays to study global expression are readily available. Furthermore, responses to specific bacterial gene products can be assessed, by comparing wild type and mutant strains.