Microbial production of dicarboxylic acids

Dicarboxylic acids are important industrial chemicals currently produced from petroleum using ecologically damaging manufacturing methods; furthermore, dicarboxylic acid prices are rising with increasing petroleum feedstock prices. Lygos is developing microbial hosts for the cost-competitive production of dicarboxylic acids from renewable feedstocks, including cellulosic hydrolysate. The combined Phase I/II approach is the development and use of a high-throughput dicarboxylic acid screen to assay for improved dicarboxylic acid production from engineered microbes. In Phase I, we constructed and characterized three dicarboxylic acid screens applicable for short- to medium-chain microbially produced diacids (up to C7). The screens are based on microbial sensing of exogenous dicarboxylic acid and an associated increase in a colorimetric reporter output. The dicarboxylic acid screen will now be implemented as a high-throughput assay for improved dicarboxylic acid production in engineered microbes. Combinatorial libraries of engineered proteins and metabolic pathways will be tested for improvements in strain yield, titer, and productivity. Dicarboxylic acid production in the evolved strain will be also demonstrated using a cellulosic hydrolysate sugar source. Commercial Applications and Other Benefits: Dicarboxylic acids are high-value chemicals used in the manufacturing of commodity and specialty goods. Lygos evolved microbial production platform will enable the cost- competitive production of diacids from renewable feedstocks, providing both an economic and environmental benefit. A key aspect of the grant effort is the production of diacids using cellulose-derived sugars.