Adaptation in a mouse colony monoassociated with Escherichia coli K-12 for more than 1,000 days.

Journal Article (Journal Article)

Although mice associated with a single bacterial species have been used to provide a simple model for analysis of host-bacteria relationships, bacteria have been shown to display adaptability when grown in a variety of novel environments. In this study, changes associated with the host-bacterium relationship in mice monoassociated with Escherichia coli K-12 over a period of 1,031 days were evaluated. After 80 days, phenotypic diversification of E. coli was observed, with the colonizing bacteria having a broader distribution of growth rates in the laboratory than the parent E. coli. After 1,031 days, which included three generations of mice and an estimated 20,000 generations of E. coli, the initially homogeneous bacteria colonizing the mice had evolved to have widely different growth rates on agar, a potential decrease in tendency for spontaneous lysis in vivo, and an increased tendency for spontaneous lysis in vitro. Importantly, mice at the end of the experiment were colonized at an average density of bacteria that was more than 3-fold greater than mice colonized on day 80. Evaluation of selected isolates on day 1,031 revealed unique restriction endonuclease patterns and differences between isolates in expression of more than 10% of the proteins identified by two-dimensional electrophoresis, suggesting complex changes underlying the evolution of diversity during the experiment. These results suggest that monoassociated mice might be used as a tool for characterizing niches occupied by the intestinal flora and potentially as a method of targeting the evolution of bacteria for applications in biotechnology.

Full Text

Duke Authors

Cited Authors

  • Lee, SM; Wyse, A; Lesher, A; Everett, ML; Lou, L; Holzknecht, ZE; Whitesides, JF; Spears, PA; Bowles, DE; Lin, SS; Tonkonogy, SL; Orndorff, PE; Bollinger, RR; Parker, W

Published Date

  • July 2010

Published In

Volume / Issue

  • 76 / 14

Start / End Page

  • 4655 - 4663

PubMed ID

  • 20472724

Pubmed Central ID

  • PMC2901717

Electronic International Standard Serial Number (EISSN)

  • 1098-5336

Digital Object Identifier (DOI)

  • 10.1128/AEM.00358-10


  • eng

Conference Location

  • United States