Date of Award
Program or Major
Master of Science
Vaughn S Cooper
I investigated the ability of Burkholderia cenocepacia, an opportunistic bacterial pathogen, to adapt to a host. Studies have identified trade-offs associated with environmental adaptation, but few have investigated host adaptation. Consequently, I studied effects of adaptation by B. cenocepacia to onions (Allium cepa) on the ability to kill Caenorhabditis elegans. I hypothesized that adaptation to onions would reduce virulence in C. elegans. I evolved twelve populations of bacteria in onion tissue medium for 500 generations. Then, I quantified fitness differences between evolved and ancestral populations by direct competition, having developed molecular marking techniques to discriminate among competitors. Competitions revealed fitness increases in nine populations. Next, I measured virulence against C. elegans of each population and observed a reduced worm killing ability. I also quantified pleiotropic effects of adaptation related to virulence. In conclusion, I supported that adaptation of B. cenocepacia to one host resulted in decreased virulence in another host.
Ellis, Crystal Nicole, "The experimental evolution of host adaptation of the emerging pathogen Burkholderia cenocepacia" (2008). Master's Theses and Capstones. 363.