SBIR Phase I: Live-cell metabolite sensors for improving biofuel production

This Small Business Innovation Research (SBIR) Phase I project involves the development of fluorescent metabolite sensors that enable high-throughput screening of genetically improved biofuel-producing cells. Currently, there are no analytical technologies that can screen large cell populations to identify metabolically superior cells for the purpose of improving biofuel production. This project will identify RNA aptamers that can selectively bind pyruvate and phosphoenolpyruvate, two essential intermediates in the metabolic pathways that generate sugar-derived and cellulosic biofuel. The identified aptamers will be designed in conjunction with reporter RNA tags to generate sensitive fluorescent biosensors that can measure real-time pyruvate and PEP metabolism in metabolically engineered host strains. The resulting fluorescent metabolite sensors address an unmet need in the biofuel technology space and will result in the development of a high-throughput screening strategy for improved biofuel production. This screening approach would allow hundreds, thousands, or even more conditions to be rapidly screened to identify and optimize conditions for culturing microorganisms. Additionally, this screening approach would allow metabolic engineered mutants to be readily screened and isolated, resulting in new mutant strains with higher metabolic rate and better tolerance to high concentrations of substrates and products. The broader impact/commercial potential of this project will be faster and cheaper generation of biofuels that could eventually replace fossil fuels as the major energy supply. Limited fossil oil resources, national security, and environmental concerns have been major drivers in the development of biofuels as alternative and renewable energy sources. Currently, sugar-derived ethanol is one of the only two renewable biofuels that is produced at a large scale with global ethanol production reaching 23.4 billion gallons a year in 2011. However, concerns with raising crop price and sustainability have propelled the explorations of ethanol production from cellulosic feedstock as well as algaculture. Although cellulosic and algae-based ethanol productions have been demonstrated at the pilot level, significant scientific research is still needed in order to transform current production methods into a cost-effective, commercial-scale ethanol production platform. New screening tools that enable microorganisms that produce higher target molecules at various culture conditions and genetic modifications to be identified with unprecedented speed has the potential to markedly impact the yields of biofuel production, which will result in lower cost on biofuel production and help make sustainable biofuels more commercially available.