S21: Using synthetic and systems biology to increase farnesene yield of engineered Saccharomyces cerevisiae

Yeast has been engineered to produce various terpenes, including the 15-carbon olefin, farnesene, a renewable alternative to petroleum. Farnesene can be polymerized into products useful to the cosmetics, lubricants and plastics industries, or hydrogenated into a drop-in replacement for petroleum diesel.  Using high throughput culturing and screening, combined with both whole cell mutagenesis and automated strain engineering, farnesene yield was increased significantly in only two years. Concurrently, mutations responsible for steps of improvement in the strain lineage were identified by genome sequencing and swapping of candidate alleles. Sequential introduction of these causal mutations into various strain backgrounds recapitulated the high yield phenotype and revealed genetic interactions. More detail on high throughput strain improvement, automated strain engineering, and the identification and use of causal mutations will be presented.