The first steps of adaptation of Escherichia coli to the gut are dominated by soft sweeps.

ABSTRACT: The accumulation of adaptive mutations is essential for survival in novel environments. However, in clonal populations with a high mutational supply, the power of natural selection is expected to be limited. This is due to clonal interference--the competition of clones carrying different beneficial mutations--which leads to the loss of many small effect mutations and fixation of large effect ones. If interference is abundant, then mechanisms for horizontal transfer of genes, which allow the immediate combination of beneficial alleles in a single background, are expected to evolve. However, the relevance of interference in natural complex environments, such as the gut, is poorly known. To address this issue, we have developed an experimental system which allows to uncover the nature of the

SUBMITTER: Barroso-Batista J 

PROVIDER: S-EPMC3945185 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature