Date on Master's Thesis/Doctoral Dissertation


Document Type

Master's Thesis

Degree Name




Committee Chair

Perlin, Michael H.

Author's Keywords

Salmonella Typhimurium; Ampicillin; Murine model


Drug resistance in microorganisms; Salmonella typhimurium


Salmonella enterica serovar Typhimurium is an enteric pathogen capable of infecting a wide range of hosts. The manner in which this pathogen is able to interact with its host is difficult to define, as is the case with most microbes. Through the use of alternate sigma factors and other regulatory processes, S. Typhimurium is able to invade host cells to establish systemic infections, and survive the assaults of the host immune system. While most strains of S. Typhimurium are typically ampicillin sensitive, within the host, survival inside host cells may provide an escape from many antibiotics. Previous research demonstrated that co-culture with ampicillin resistant strains of Escherichia coli is able to provide protection for sensitive S. Typhimurium. The current study was an attempt to model this relationship within the host. While S. Typhimurium was able to grow within murine hosts in the presence of ampicillin, it is unclear whether this resistance is from coinfection with a resistant strain of E. coli or from the ability of S. Typhimurium to avoid destruction by antibiotics by invading host cells.