Experimental evolution of Legionella pneumophila in mouse macrophages leads to strains with altered determinants of environmental survival.

ABSTRACT: The Gram-negative bacterium, Legionella pneumophila, is a protozoan parasite and accidental intracellular pathogen of humans. We propose a model in which cycling through multiple protozoan hosts in the environment holds L. pneumophila in a state of evolutionary stasis as a broad host-range pathogen. Using an experimental evolution approach, we tested this hypothesis by restricting L. pneumophila to growth within mouse macrophages for hundreds of generations. Whole-genome resequencing and high-throughput genotyping identified several parallel adaptive mutations and population dynamics that led to improved replication within macrophages. Based on these results, we provide a detailed view of the population dynamics of an experimentally evolving bacterial population, punctuated by frequent ins

SUBMITTER: Ensminger AW 

PROVIDER: S-EPMC3364954 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature