Fitness effects of advantageous mutations in evolving Escherichia coli populations.

ABSTRACT: The central role of beneficial mutations for adaptive processes in natural populations is well established. Thus, there has been a long-standing interest to study the nature of beneficial mutations. Their low frequency, however, has made this class of mutations almost inaccessible for systematic studies. In the absence of experimental data, the distribution of the fitness effects of beneficial mutations was assumed to resemble that of deleterious mutations. For an experimental proof of this assumption, we used a novel marker system to trace adaptive events in an evolving Escherichia coli culture and to determine the selective advantage of those beneficial mutations. Ten parallel cultures were propagated for about 1,000 generations by serial transfer, and 66 adaptive events were identified.

SUBMITTER: Imhof M 

PROVIDER: S-EPMC14717 | biostudies-literature | 2001 Jan

REPOSITORIES: biostudies-literature