**SSA**Characterisation of type III effector proteins from A/E pathogens.

Human infections caused by Escherichia coli present a significant burden to public health. For example, several recent outbreaks can be traced back to contaminated produce that had been in contact with cattle, the natural reservoir for some pathogenic E. coli strains. These bacteria produce molecular agents that allow them to target and manipulate gut tissue in humans, leading to pathology. One group of these agents are toxins, or effector proteins, that are injected into gut cells by the bacterium via a macromolecular complex termed the type III secretion system (T3SS). This project will focus on uncharacterised effector proteins produced by pathogenic E. coli strains, as well as Citrobacter rodentium, which is a mouse-restricted pathogen that shares a number of virulence determinants with human pathogenic E. coli strains. We aim to determine the specific host pathways that are being targeted by the bacterium, the molecular basis for these interactions, and demonstrate the importance of effectors in a mouse model of infection. Understanding the role of each of these toxins in infection is critical for developing novel therapeutic agents and effectively dealing with outbreaks.