The fitness effects of a point mutation in Escherichia coli change with founding population density.

ABSTRACT: Although intraspecific competition plays a seminal role in organismal evolution, little is known about the fitness effects of mutations at different population densities. We identified a point mutation in the cyclic AMP receptor protein (CRP) gene in Escherichia coli that confers significantly higher fitness than the wildtype at low founding population density, but significantly lower fitness at high founding density. Because CRP is a transcription factor that regulates the expression of nearly 500 genes, we compared global gene expression profiles of the mutant and wildtype strains. This mutation (S63F) does not affect expression of crp itself, but it does significantly affect expression of 170 and 157 genes at high and low founding density, respectively. Interestingly, acid resistance ge

SUBMITTER: Cao H 

PROVIDER: S-EPMC4989268 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature