Improving Clostridial ABE Fermentation with Signaling Molecules

Extracellular signaling small molecules (SSMs) are commonly used by bacteria to access information about both the intracellular physiological status and extracellular environment. These small molecules are critical in controlling complex biological processes including morphological differentiation, multicellularity, biofilm formation, virulence, motility, stress response, substrate usage, and secondary metabolite production. Despite the importance of SSMs in bacterial physiology and behavior, little is known about SSMs in clostridia. Although genomic analysis indicates the presence of SSMs in this genus, little work has been done to experimentally investigate these molecules. In order to improve the performance of clostridial ABE (acetone-butanol-ethanol) fermentation, it is crucial to unveil the identity and function of hidden SSMs in relevant Clostridium species. The governing hypothesis of this work is that SSMs can be used to manipulate clostridial fermentations by controlling cell density, cellular development, substrate usage, solvent production, and solvent tolerance. This project will use comprehensive approaches: activity-based profiling and targeted genome mining to unveil SSMs of clostridia, with the goal of improving ABE fermentation performance.