Developing the Fluoride Riboswitch as a Technology to Combat Excess Water Fluoridation

Fluoride is present in all bodies of water: oceans, rivers, lakes, and groundwater. The extent to which fluoride is present depends on the amount of sediments or volcanic rocks being eroded in the area. However, when fluoride concentrations are at the toxic level health concerns can arise. Fluoride concentrations at or above 1 mg F per kg of body weight are considered poisonous. Ingesting this amount in one sitting requires immediate medical attention. While constantly being exposed to more than 6 mg of fluoride every day can lead to dental and skeletal fluorosis, in which the teeth and bones decay and deform. More severely, doses above 4.5 mg per kg body weight can cause developmental and reproductive concerns. Meaning fluoride concentrations can affect the growth and the IQ of people. In countries like China, India, and Sri Lanka, water sources are decentralized and residents are suffering from these effects of excess fluoridation.

In order to combat excess fluoride in water in a cost effective manner, we envision developing technologies using the fluoride riboswitch - a strand of mRNA that regulates downstream gene expression. To this end, we designed a method to characterize the responsiveness of fluoride riboswitches that is amenable to high-throughput screening and affinity maturation. Our system is called the "Fluoride Riboswitch Regulated Chloramphenicol Acetyltransferase Operon" (CHOP) which allows bacteria to grow on the antibiotic chloramphenicol only in the presence of fluoride. This system can be used to identify riboswitches with higher responsiveness to fluoride. Learn more about our project and discoveries in our wiki!