Identifying the Adaptive Mutations that Allow for Increased Biofilm Formation by Burkholderia cenocepacia
Populations of B. cenocepacia evolved in the laboratory (by Steffen Poltak) under conditions favoring biofilms produce significantly more biofilm than the ancestral isolate. We hypothesize that these hyper-biofilm forming evolved populations are similar to those in chronic stages of infection that would be isolated from the lungs of CF patients. Our preliminary data on the physiology of the evolved populations support this hypothesis, but the underlying genetic mechanisms are unknown. These laboratory-evolved bacteria can now be used as a tool for tracking the evolution of a chronic infection.
As my thesis project, I am determining some of the molecular mechanisms by which B. cenocepacia has evolved into an excellent biofilm-former, which may be the same mechanisms by which this pathogen evolves in the CF lung. I have started a mutant library using a trimethoprim resistant Tn5-based construct for evaluating mutations conferring an increased biofilm phenotype and am also working on genetic complementations of a few of our experimentally evolved isolates for which we have sequence data.
