Dr. Lynn Hancock's laboratory
"My lab is interested in understanding the mechanisms of pathogenesis for the opportunistic bacterial pathogen, Enterococcus faecalis. This organism is a leading cause of hospital acquired infections ranging from urinary tract infection to life threatening endocarditis. As a commensal organism of the colon, E. faecalis must compete with other resident microbes for limited nutrients. Enterococci have adapted well to life as a gastrointestinal tract commensal, and have been found in fecal samples of nearly all mammals and insects. Recently, it has been shown that E. faecalis produces measurable amounts of extracellular superoxide as part of its metabolic processes. This highly reactive oxygen species has also been shown to damage DNA of cultured cells derived from the colonic epithelium. DNA damage resulting from the production of extracellular superoxide by E. faecalis could contribute to the development of colonic polyps and subsequent colonic cancer. A better understanding of the factors that E. faecalis uses to survive the harsh confines of the colon, where oxygen is limited and nutrients are scarce, may enable us to devise strategies to prevent colonization. We are presently examining factors that enterococci use to establish infections in extra-intestinal sites, but these same factors may aid in the colonization process. Interfering with E. faecalis colonization may be a novel means of reducing the amount of damaging agents that our bodies encounter in the colon, and would likely reduce the number of cases of colon cancer attributed to a microbial factor."
