Engineering yeast as platform strains to convert food waste into high-value chemicals

Since Neolithic times, microbes have been exploited and utilized for the production of food and commodity products. Recent advances in genetic engineering and biotechnology allow directed creation of cell factories that produce a plethora of bio‐based products (e.g. fuels, chemicals, plastics and pharmaceuticals). In this PhD project, we aim to create Saccharomyces cerevisiae platform strains that produce high-value chemicals (i.e. isoamyl aldehyde and lauric acid) from food waste streams. The strategy to create these platform strains is the de novo synthesis of an artificial NeoChromosome, carrying many ‘functional analogues’ of each step of the heterologous pathway required to synthesize these products, together with features that make this NeoChromosome hyper-evolvable (recombination-based pathway optimization and confined mutagenesis). Together, this allows to create vast mutant/variant libraries of S. cerevisiae strains with different combinations and mutations. This project will employ the microfluidics platform developed by Imec to screen and select variants that can produce high amounts of the green chemicals. In a second part of the project, a number of low-value food waste will be selected, analyzed and pretreated to assess their suitability as microbial feedstock. Therefore, the growth of the optimized platform strains on selected feedstock will be evaluated, up-cycling food waste into high-value chemicals.