Executive Summary : | The project aims to create modular communities of recombinant microbial strains that optimize each member strain for specific function, reducing the metabolic burden on cells and enabling greater flexibility in consortia design. This approach will be tested to design a cellulase cocktail to convert biomass to sugars efficiently. The current approach of varying each component of the cocktail is inefficient and does not contribute to understanding the synergistic action of many enzymes toward degrading biomass. The consortium will consist of two strains of E. coli: sender cells to hydrolyze cellulose to cellobiose and receiver cells to convert cellobiose to glucose using the acyl-homoserine lactone (AHL) quorum-sensing system. The Lux QS system with LuxI and LuxR genes and Plux promoter will be used for communication between the sender and receiver cells. To improve the consortium and make it self-regulated, E. coli's native Autoinducer 2 (AI2) based QS lsr promoter will be incorporated in place of the IPTG inducible promoter. A cellobiose-sensitive promoter will be used to aid communication between the strains, eliminating the requirement for cells to produce different quorum-sensing molecules. This project aims to develop computational and synthetic biology tools to optimize metabolic flux in genetically tractable microorganisms such as Escherichia coli and carry it forward to other strains, including gram-positive bacteria. |