Uropathogenic Escherichia coli (UPEC) are a major cause of urinary tract infections (UTI) and sepsis. Recently, a highly virulent clone of UPEC (E. coli ST131) that is resistant to multiple types of antibiotics has emerged worldwide. This project addresses the mechanisms by which E. coli ST131 can colonise the urinary tract and cause disease. The outcomes of this project will be a better understanding of how E. coli ST131 causes disease, and potentially new treatment regimes for UTI.