Developing the Fluoride Riboswitch as a Technology to Combat Excess Fluoridation

Fluoride is present in all bodies of water. Within the oceans, rivers, lakes, and groundwater, the mineral is existent and the extent to which fluoride is present depends on the amount of sediments or volcanic rocks being eroded in the area. It is when fluoride concentrations are at the toxic level when 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 10 mg l-1 to 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 kg-1 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 engineered a fluoride riboswitch - a strand of mRNA that regulates gene expression. When fluoride, the ligand for the fluoride riboswitch, is present, the terminator does not form, allowing the gene downstream to be expressed. We designed a method to find new riboswitches with higher affinity to fluoride and to measure concentrations of fluoride; our Chloramphenicol Operon (CHOP) can be used to do so since the growth of CHOP is dependent on the activation growth of the fluoride riboswitch on certain concentration of fluoride. Learn more about our project and discoveries in our wiki!