Research in our lab seeks to understand the means by which the bacterial pathogen Salmonella responds to its environment to express traits necessary for survival and virulence. One major research focus describes the cues within an animal host that induce virulence gene expression. The chemical environment of the intestine is largely defined by the bacteria that normally reside there and the byproducts of their metabolism. Our work shows that the fatty acids of the intestinal tract, produced by these resident bacteria, affect Salmonella virulence in a complex way: the fatty acid composition of the ileum, where Salmonella normally invades, promotes the expression of genes required for virulence, while colonic conditions have the opposite effect. Our work therefore examines how changes in the environment of the intestine affect the virulence of Salmonella, and how these conditions might be manipulated to reduce disease. We additionally study the means by which Salmonella can survive and proliferate in and on produce plants, as these agricultural products present a threat for the transfer of this pathogens to people. Our work in this area focuses on defining the genes and metabolic process required for Salmonella to survive in tomatoes, and in defining means by which the plant responds to this pathogen.