Modulation of host cell signalling by enteropathogenic and Shiga toxin-producing Escherichia coli

The majority of Escherichia coli strains are harmless symbionts in the inte stinal tract. However, there are several pathogenic forms, which are respon sible for various diseases in humans and live stock. In this review we disc uss the interactions between Shiga toxin-producing E. coli and enteropathog enic E. coli and their target host cells, describing their strategies to ac tivate specific cellular signalling pathways which lead to subversion of cr itical physiological functions. We mainly concentrate on those pathogenic m echanisms that are dependent on a functional type III secretion system, but we also briefly discuss additional factors that contribute to the specific pathogenic profiles of Shiga toxin-producing E. coli and enteropathogenic E. coli.