The P. putida genome also was compared to that of other species to reveal details about the microbe's evolutionary history. Perhaps the most revealing comparison was with the genome of another member of the Pseudomonas genus P. aeruginosa, which is an opportunistic pathogen and the leading cause of death for cystic fibrosis patients.
TIGR evolutionary biologist Jonathan Eisen said, "Such comparisons among closely related species with different biological properties are invaluable in learning about the biology of each species. In this case it allows us to better identify the features in the P. aeruginosa genome that contribute to making it a pathogen."
An analysis by Tuemmler and Christian Weinel of the MHH identified numerous chemosensory systems, cell attachment factors, and transport systems in P. putida that had been thought to be involved in virulence in P. aeruginosa. For example the KT2440 (P. putida) genome contains a chromosomal region that is present in 85% of P. aeruginosa clinical isolates from sepsis and urinary tract infections. "That suggests that those genes many not be specific for virulence," said Eisen. The researchers did, however, find many genes in P. aeruginosa and not P. putida that had not previously been identified as candidates for being involved in pathogenicity. The identification of such genes may help biomedical researchers pinpoint potential targets for developing drugs or vaccines against this pathogen.