Interaction of enteropathogenicEscherichia coli with host epithelial cells

EnteropathogenicEscherichia coli (EPEC) causes severe diarrhea in young children. Upon infection, EPEC induces the assembly of highly organized pedestal-like actin structures in host epithelial cells. All the EPEC genes that are involved in inducing formation of actin pedestals are located in a unique 35 kbp chromosomal pathogenicity island, termed LEE. These genes include thesep genes that encode components of type III protein secretion system, and genes that encode proteins secreted by this system, theesp genes. This protein secretion system is activated upon contact with the host cell, resulting in increased secretion of Esp proteins. Some of these Esp proteins form the translocation apparatus while others are translocated into the cytoplasm of the host cell. Concerted activity of the LEE genes including theeae, esp and thesep genes is needed to trigger signal transduction in the host cell which results in formation of an actin pedestal. Presented at the1st International Minisymposium on Cellular Microbiology: Cell Biology and Signalization in Host-Pathogen Interactions, Prague, October 6, 1997.