Summer Research Description: Urinary tract infections (UTIs) are commonly acquired in the community and in the hospital. In diabetic populations, the risk of developing a UTI is double of that of non-diabetics. This increased risk is not associated with higher urine glucose levels. Uropathogenic Escherichia coli (UPEC) cause the majority of UTIs and have the ability to attach to the bladder surface using adhesive fibers and form biofilms both on the surface of and within bladder cells. UPEC have sensory devices that respond to serine and pyruvate. These are the two-component systems YpdAB (senses pyruvate) and YehUT (senses serine). Interestingly, diabetics secrete 2-3-fold more pyruvate and serine in their urine compared to non-diabetics. We hypothesize that higher serine and pyruvate in the urine of diabetics is sensed by UPEC and contributes to increased UTI. We will test how fluctuations in serine/pyruvate impact biofilm formation and adhesive fiber expression in mutants lacking YehUT or YpdAB using in vitro biofilm assays and immunoblot analyses. These studies will begin to elucidate the role of YpdAB and/or YehUT in metabolite sensing during processes that are important for UTI.