Eyeing Pathogen’s Adaptive Evolution: Different “Stories” per Infected Organs

Seminar

Title: Eyeing Pathogen’s Adaptive Evolution: Different “Stories” per Infected Organs

Speaker: Joao Paulo Gomes

Affiliation: Departament of Infeccious Diseases, Instituto Nacional de Saúde Dr. Ricardo Jorge, Lisbon, Portugal

Host: Jaime Mota

Abstract:

When two species interact with each other, as a pathogen and the human being, a never-ending reciprocal and dynamic adaptation process takes place. Whereas the “goal” of the human being is to try to avoid, solve or minimize the infection, the “goal” of the pathogen is to deal with this constant host environmental and immune pressure, through genomic evolutionary changes in order to win this “arms-race”. Still, we wonder if distinct arms-races may occur inside the same host when a pathogen is able to infect different organs. We tested this hypothesis using the most prevalent sexually transmitted bacterial pathogen worldwide, Chlamydia trachomatis, as model species, comprising 15 serovars with specific organ-appetence: eyes, genitalia and lymph nodes. We have demonstrated that same-species with different organ-appetence, present a distinct evolutionary pattern. Genomic differences relied mostly on nucleotide changes dispersed throughout the whole chromosome, besides their occurrence in putative virulence or colonization factors. Our results suggest that the C. trachomatis diversity relies mainly on evolutionary adaptation to physiologically distinct biological niches and discard the genetic drift as the dominant evolutionary driving force. Eying these tissue-specific adaptive evolution scenario is crucial for the understanding of how pathogen and host interact on the course of infectious diseases.

 
These are some of the recent papers of João Paulo Gomes:

• Nunes A, Nogueira PJ, Borrego MJ, Gomes JP. Chlamydia trachomatis diversity viewed as a tissue-specific coevolutionary arms race. Genome Biol. 2008 Oct 23;9(10):R153. [Epub ahead of print]
• Nunes A, Gomes JP, Mead S, Florindo C, Correia H, Borrego MJ, Dean D. Comparative expression profiling of the Chlamydia trachomatis pmp gene family for clinical and reference strains. PLoS ONE. 2007 Sep 12;2(9):e878.
• Gomes JP, Bruno WJ, Nunes A, Santos N, Florindo C, Borrego MJ, Dean D. Evolution of Chlamydia trachomatis diversity occurs by widespread interstrain recombination involving hotspots. Genome Res. 2007 Jan;17(1):50-60. Epub 2006 Nov 7.