This year the Northwestern iGEM team has decided to focus on oral health care as the theme of our project. It has been well characterized that lactic acid secreted by natural bacteria in the human mouth decreases pH, leading to cavity formation. The enamel demineralization threshold is known to be around pH 5.5. Previous research has found that the genes asr and gadA are highly expressed near pH 5.5 and below. Our project aims to take a two-pronged approach at combating the natural lactic acid secretion. We plan to create a promoter that is always on at a basal level as well as one that is induced to express at a high level as a result of low pH. This project will lay the foundation for a significant amount of research as the dual-state promoter that we develop could then be incorporated with a gene related to lactic acid catabolism or neutralization.
Summary of Problem
Following any meals, the pH within the mouth usually drop substantially which can lead to cavities.
pH
The first step in combating cavities is to create a bacteria that can detect pH.
Dual State Promoter
In order to be able to produce quick response in addition to a basal level, the team has designed the dual state promoter.
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