In order to survive within a host organism, pathogenic bacteria have evolved flexible metabolic pathways and defense mechanisms. Dr. Frawley uses the model pathogen Salmonella Typhimurium to study how bacteria respond to host-generated chemical defenses such as nitric oxide and hydrogen peroxide. Many key enzymes and pathways are directly inhibited by peroxide and nitric oxide so, in order to survive, bacteria must find ways to adapt to, and repair damage that occurs. Dr. Frawley is particularly interested in how nitric oxide affects metal-containing proteins and how metal transport impacts bacterial stress resistance. Current work focuses on the roles that bacterial copper and manganese transporters play during infection and how the function of these proteins is regulated.