Using Kinetics of Growth and Sugar Fermentation By Vibrio Cholerae to Identify Inhibitors of the Phosphoenolpyruvate-Carbohydrate Phosphotransferase System

The phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS) is a multistep chemical process which regulates the intake and use of carbohydrates by bacteria. When bacteria grow through the use of sugars and other nutrients they may form a biofilm, a layer of bacterial cells that grow attached to one another in a film. The PTS not only controls the sugar intake of bacteria but also regulates several cellular functions such as chemotaxis, catabolite repression and the aforementioned biofilm formation. We hypothesize that given the established connection between PTS activity and biofilm formation in bacterial species, the identification of small-molecule that can interfere with PTS activity will suggest new tools and approaches for the control of microbial biofilms. In order to do this, we use a screening assay for Vibrio cholerae fermentation of sugars that are transported by the PTS. This screen was then used to dozens of chemical compounds which were selected for their physiochemical properties, such as solubility, decreased toxicity, and increased stability. For the screen assay, a V. cholerae O139 strain, MO10, growing in the absence of chemical compounds served as a negative compound. An altered strain, which lacked PTS activity, served as a positive control. Preliminary data suggests that some of the compounds screened exhibit antibacterial activity, while others seem to interfere with the ability of Vibrio to ferment sugars. This interference may be due to interaction with the PTS and will be further investigated. Success of this project will result in the identification and characterization of antimicrobial compounds that inhibit the bacterial PTS system and regulate biofilm formation. This may lead to the development of novel microbial control strategies with applications in engineering, physical, biological, medical, and pharmaceutical sciences.