Crispr-Cas Assisted Metabolic Engineering of Lipid Metabolism in Saccharomyces Cerevisiae

Engineering microbes for industrial-scale production of valuable chemicals involves extensive modulation of cellular metabolism for enhanced productivity. Genome engineering to introduce different types of genetic modifications including gene deletion, overexpression, and exact regulation is extremely important to improve pathway efficiency and product yield. In this context, CRISPR/Cas offers a powerful time efficient tool for targeting specific genomic loci of interest, which can conceivably be used to tune different gene expressions. As Saccharomyces cerevisiae is a well-studied industrially robust microorganism and the overall metabolism, including the lipid metabolism, is well known, it is feasible to engineer lipid metabolism for overproduction of oleochemicals reaching industrial standards. Here we use CRISPR/Cas to engineer the lipid metabolism of S. cerevisiae towards accumulation of triglycerides. Triacylglycerols (TAGs) are key molecules for the cell as they function as energy storage and also as feedstock for the production of oleochemicals and biodiesel. In order to achieve industrially relevant titers of TAGs, we regulated a series of genes involved in various pathways such as beta-oxidation, lipid biosynthesis, lipid droplet formation and autophagy to prevent these lipids from mobilisation/degradation by the cell. Ultimately, the knowledge obtained from the different strains generated will provide a better understanding on how lipid metabolism is regulated, and how it affects the cell´s phenotype, lipid composition, growth and size.