Boostingmethionine levels for enhanced nutritional profile of yeast co-products used in animal feed

This project will develop high methionine yeast strains to improve the nutritional content of yeast- based co-products. The US corn ethanol industry produces millions of tons of nutritional co- products increasingly with high protein/low fiber content which are better suited for monogastricfeeds. The residual yeast biomass after ethanol fermentation represents a significant portion of theseco-products and is an attractive target for nutritional improvements.In Phase I of this proposal we will establish the feasibility of using our proprietary combinatorialsynthetic biology technology Function Generatorâ„¢ to discover a wide range of novel geneticsolutions that improve methionine accumulation in yeast. These new trait genes will beincorporated into a commercial yeast strain and evaluated for methionine accumulation. Validatedmethionine-stimulating genes will be licensed to yeast manufacturers to create high methionineyeast strains which will in turn allow their customers to generate higher value co-products.This project addresses numerous USDA priorities by improving the cost and sustainability ofmethionine and ultimately of meat production. Every year over one megaton of methionine isproduced chemically from toxic petrochemical feedstocks for use as an animal feed supplement.Without proper methionine supplementation the health and growth of animals are severelyimpacted. Furthermore unbalanced amino acid profiles in feed lead to excretion of excess nitrogenin animal waste increasing the environmental impact of meat production. This project will providea low cost natural solution to enriching the methionine content in widely used animal feedingredients with the potential to displace 100's of kilotons of chemical methionine.