Resumen

SOUZA, Valeria et al. Ecología evolutiva de escherichia coli. INCI [online]. 2001, vol.26, n.10, pp.513-517. ISSN 0378-1844.

Escherichia coli is the best known organism in terms of its genetics and physiology. However, very little is understood about its ecology and evolutionary biology. In this paper we review some aspects of its biology, genomics, ecology, and population genetics. Classic studies, mostly based on human strains, suggested that E. coli was a clonal bacteria showing little recombination. We have built and analyzed a collection called IECOL, with over 2000 bacterial strains from animals from several places in the world, humans from Mexico and wild strains from different environments. In this study, we report population genetics and molecular evolution data from E. coli in this collection. These results, together with recently published studies, show that E. coli is a very diverse organism with a dynamic genome. Recombination is important and the successful combinations can spread in an epidemic way within human and animal populations, giving a false signal of clonality. Finally, the potential use of the IECOL collection is illustrated using examples of our studies about the evolution of mutation rates and pathogenic genes.

Palabras clave : Escherichia coli; Genética de Poblaciones; Ecología de Poblaciones; Evolución de Patogénesis; Bacterias.