Our initial goal for the project was to design a system that, when cancer cells are detected, produced a β-galactosidase reporter that would cause a color change in the stool. We initially explored two methods of detection: FimH/OxyR mediated response and quorum sensing mediated response. FimH is an E. coli fimbriae capping protein. OxyR is a transcription factor that up-regulates lacZα production through FimH binding and increase H2O2. Team discussions, meetings with our mentors and microbiology experts, and examining the current literature led us to pursue this path for our project.