Adaptive benefits from small mutation supplies in an antibiotic resistance enzyme.

ABSTRACT: Populations with large mutation supplies adapt via the "greedy" substitution of the fittest genotype available, leading to fast and repeatable short-term responses. At longer time scales, smaller mutation supplies may in theory lead to larger improvements when distant high-fitness genotypes more readily evolve from lower-fitness intermediates. Here we test for long-term adaptive benefits from small mutation supplies using in vitro evolution of an antibiotic-degrading enzyme in the presence of a novel antibiotic. Consistent with predictions, large mutant libraries cause rapid initial adaptation via the substitution of cohorts of mutations, but show later deceleration and convergence. Smaller libraries show on average smaller initial, but also more variable, improvements, with two lines yiel

SUBMITTER: Salverda MLM 

PROVIDER: S-EPMC5715772 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature