Evolutionary Dynamics of Asexual Hypermutators Adapting to a Novel Environment.

ABSTRACT: How microbes adapt to a novel environment is a central question in evolutionary biology. Although adaptive evolution must be fueled by beneficial mutations, whether higher mutation rates facilitate the rate of adaptive evolution remains unclear. To address this question, we cultured Escherichia coli hypermutating populations, in which a defective methyl-directed mismatch repair pathway causes a 140-fold increase in single-nucleotide mutation rates. In parallel with wild-type E. coli, populations were cultured in tubes containing Luria-Bertani broth, a complex medium known to promote the evolution of subpopulation structure. After 900 days of evolution, in three transfer schemes with different population-size bottlenecks, hypermutators always exhibited similar levels of improved fitness as

SUBMITTER: Ho WC 

PROVIDER: S-EPMC8643662 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature