The cost of enzymes for converting plant biomass materials to fermentable sugars is a major bottleneck in the development of a viable lignocellulosic ethanol industry. Commercial enzyme mixtures currently available, which are mainly from species of Trichoderma and Aspergillus, are complex and poorly defined. In order to lower the cost of enzymes we need enzyme cocktails of higher specific activity. Our approach to this problem is to use pure enzymes to design synthetic, defined, and optimized mixtures. In this way we learn which enzymes are important for biomass deconstruction and in what optimal proportions. Synthetic mixtures also provide a platform that can be used to find new accessory enzymes and better examples of current enzymes. We have made synthetic mixtures optimized for release of glucose and xylose from alkaline pretreated feedstocks containing more than 16 enzyme components using statistical design of experiment and robotic liquid handling systems. To date, our enzymes have been derived from Trichoderma reesei, but novel enzymes that act synergistically with those of Trichoderma can be discovered and validated with our system. . The goal of this research is to make enzyme mixtures for biomass applications that have higher specific activity and thus lower cost.
Full conference title:
26th Fungal Genetics Conference
- Fungal Genetics Conference 26th (2005)