Microbial cell factories to convert food waste into high-value chemicals (STRAINDROPS)

From early days, microbial processes have been exploited for the production of food and commodity products. The advent of genetic engineering and biotechnology has allowed the rational design of cell factories that produce biobased products from renewable feedstock. However, current approaches are often laborious and time-consuming. Recent advances in synthetic biology allow the design and construction of artificial metabolic pathways. This strategy coupled to advances in the selection of superior strains allows the generation of optimized cell factories in a high-throughput way. The aim of the proposed StrainDrops project is to develop a platform to create and select bacterial or yeast strains that produce high-value chemicals from waste streams. To demonstrate the potential of the platform, cell factories that produce high levels of α-ketoglutaric acid, isoamyl aldehyde and medium-chain fatty acids will be created. Strains producing basal levels of these compounds will first be constructed by introducing metabolic modules into chassis strains. Next, for each of the producing strains, large-scale variant libraries will be constructed using state-of-the-art approaches. A droplet microfluidics system will be developed for high-throughput screening and selection of strains with superior biocatalytic activity. The produced compounds will be isolated and catalytically converted into industriallyrelevant precursor molecules for applications in polymers, cosmetics, lubricants, detergents and feed additives. Finally, a number of low-value food waste streams will be selected, analyzed and pretreated to assess their suitability as microbial feedstock and the growth of the optimized cell factories on selected feedstock will be evaluated. At the end of this project, a platform for the production of high-value compounds will be available, allowing swift construction and deployment of cell factories for other types of valuable chemicals.