Our long-term research goal is to study the molecular mechanisms of how enteropathogenic E. coli (EPEC) causes disease. We currently have two main projects underway. The first area of study concerns the regulation of EPEC virulence factors by a novel protein called Ler. Funding for this project comes from a three-year Academic Research Enhancement Award (NIH grant 2R15AI47802-03).
|Model for Action of Ler at LEE promoters. Figure from Haack et al. (2003) Infection and Immunity 71: 384-392. Arrow notes direction of transcription.|
A second project is directed at understanding the effects of zinc on E. coli pathogenesis. It has been observed that children with diarrhea in developing countries have less severe disease if they are given zinc. This is not due to zinc deficiencies in their diets, but rather to unknown effects on the bacteria. Specifically, this project involves understanding the molecular mechanisms of how zinc down-regulates virulence gene expression in enteropathogenic E. coli and is supported by a collaborative grant with Dr. John Crane at the University of Buffalo (NIH grant 5R01AI081528-02).
The effects of zinc stress on the EPEC envelope imaged by transmission electron microscopy. Figure from Mellies et al. (2012) BMC Microbiology 12: 123. Arrow points to outer membrane blebs in (D). (A,D) Bars 1.0 μm; (B-C,D-F) Bars 0.1 μm.