SBIR Phase II: Large-scale, high-throughput optimization of gene expression in industrial yeast for improved small molecule production

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is development of a microbial technology for the conversion of low-value sugars into high-value chemicals. Most industrial chemicals produced today are derived from petroleum and other nonrenewable raw materials. The long-term growth and sustainability of the chemical industry benefits from development of new routes to existing chemicals using renewable raw materials. Furthermore, due to higher infrastructure costs and stricter environmental requirements, many chemicals that were once produced in the United States are now produced abroad. This contributes to the U.S. trade deficit. This Phase II proposal aims to develop a fermentation technology where domestically grown agricultural materials (for example, corn and waste agricultural residues) are converted into high-value chemicals. The optimized fermentation process is estimated to be cost-competitive with the incumbent petrochemical route when scaled. If successful, this proposal will facilitate growth of a domestic bio-chemical manufacturing industry, targeting the $30 billion organic acids market. This SBIR Phase II project proposes to develop large-scale, high-throughput techniques to optimize gene expression in industrial yeast. A significant problem within the field of industrial biotechnology is the ability to engineer and optimize the fermentation performance of non-academic or model microbes. Most molecular metabolic engineering tools are developed for use in two model prokaryotic and eukaryotic microbes, E. coli and S. cerevisiae, and are not suitable for use with industrially relevant microbes. Without these tools it is costly and slow to commercialize new fermentation technologies. The goal of this Phase II project is to develop and implement a set of molecular biology tools designed for acid-tolerant yeast, and working to apply them toward improving small molecule production. Specifically, the molecular biology tools are useful for tuning (up- or down-regulation) user-defined gene transcription and translation. Engineered microbes harboring the desired genetic modification(s) are assayed for improved small molecule production from sugar in small scale fermentations. Successful genetic modifications are those that result in more efficient small molecule product formation from sugar, and ideally decreased biomass formation from sugar, providing a lower production cost in a scaled, commercial process.