Streptococcus mutans is one of the most prominent oral bacteria involved in the progression of dental caries (cavities), serving as an adhesive agent in the formation of biofilms. While it is known that the commensal strains interfere with the growth of S. mutans, the antagonistic interactions are subjected to influence by environmental factors, including oxygen availability, pH, and carbohydrate presence. Using a S. mutans strain, UA159, this project aims to screen a series of commensal patient isolates of oral streptococcal species in the presence of amino sugars N-acetylglucosamine (GlcNAc) and glucose (Glc) by measurements of fluorescence, optical density, and colony-forming unit enumeration. The amino sugars serve as biofilm systems that more closely resemble the oral environment, aiming to assess the following hypothesis: the presence of amino sugars will enhance the ability of the commensals to persist with and antagonize S. mutans in mixed-species biofilms. The future of this project revolves around tackling the genetic implications of the bacterial relationship – specifically, analyzing the changes in the genetic makeup of the commensal strains as a result of the interactions for future medicinal developments.