Engineering a Synthetic Microbial Consortium for Efficient Production of Water Retaining Biopolymers via in-situ Precursor Production

Synergistic microbial communities are ubiquitous in nature and exhibit appealing features, such as sophisticated metabolic capabilities and robustness. This has inspired fast-growing interest in engineering synthetic microbial consortia for bioprocessing and biotechnology development. However, despite the potential advantages offered by microbial consortia, there are relatively few reports of their use in real-world applications. In this work, we have constructed a synthetic fungal-bacterial consortium for the efficient production of water retaining biopolymers with diverse commercial applications from low-cost biomass resources. Conventional fermentation methods for producing these biopolymers generally require exogenously supplied metabolic precursors, contributing to high feedstock costs. We have designed a binary consortium in which biopolymer precursors are produced in-situ from low-cost biomass materials, eliminating the need for exogenous addition. In this system, one microbial species converts biomass feedstocks into biopolymer precursors, which are subsequently co-metabolized to the final biopolymer product by a second species. Biopolymer production with the consortium has been demonstrated using biodiesel waste glycerol, a low-cost biomass resource, as the primary feedstock. Feedstock flexibility can be achieved by utilizing pre-cursor producing species with different substrate preferences, and work is currently underway to adapt the system to carbohydrate-rich biomass feedstocks.