Does experimental evolution reflect patterns in natural populations? E-coli strains from long-term studies compared with wild isolates

Souza, V; Travisano, M; Turner, PE; EGUIARTE, LE

Abstract

Our results show that experimental evolution mimics evolution in nature. In particular, only 1000 generations of periodic recombination with immigrant genotypes is enough for linkage disequilibrium values in experimental populations to change from a maximum linkage value to a value similar to the one observed in wild strains of E. coli. Our analysis suggests an analogy between the recombination experiment and the evolutionary history of E. coli; the E. coli genome is a patchwork of genes laterally inserted in a common backbone, and the experimental E. coli chromosome is a patchwork where some sites are highly prone to recombination and others are very clonal. In addition, we propose a population model for wild E. coli where gene flow (recombination and migration) are an important source of genetic variation, and where certain hosts act as selective sieves; i.e., the host digestive system allows only certain strains to adhere and prosper as resident strains generating a particular microbiota in each host. Therefore we suggest that the strains from a wide range of wild hosts from different regions of the world may present an ecotypic structure where adaptation to the host may play an important role in the population structure.

Más información

Título según WOS: ID WOS:000178390200014 Not found in local WOS DB
Título de la Revista: ANTONIE VAN LEEUWENHOEK INTERNATIONAL JOURNAL OF GENERAL AND MOLECULAR MICROBIOLOGY
Volumen: 81
Número: 1-4
Editorial: Springer
Fecha de publicación: 2002
Página de inicio: 143
Página final: 153
DOI:

10.1023/A:1020594013195

Notas: ISI