R&D Matching Grant: Differentiating Microbial Pathway and Membrane Adaptations for Enhanced Performance in Extreme Environments

There is renewed interest in the development of technologies for producing chemicals, materials, and energy from renewable resources rather than from petroleum. The production ofbio-ethanol offers considerable promise for decreasing fuel oil consumption and increasing markets for agricultural and forestry biomass. Converting this plant material to valuable products using bacteria promises to overcome some of the problems associated with currently used yeast fermentations. However, one of the barriers to using these bacteria is the relatively low ethanol tolerance that nearly all bacteria have when compared to yeast. In order to overcome this problem we need to understand the cause, but there is still relatively little detailed information on the mechanisms. These bacteria are capable of adapting to extreme environments, including higher concentrations of ethanol, but the adaptations are also not well understood. The adaptation mechanisms are important in order to effectively engineer organisms that can tolerate higher concentrations of ethanol. Growing these organisms under pressure allows us to differentiate between biochemical pathway alterations and membrane fluidity changes, whereas studying the cells in ethanol alone does not. Our proposed work will characterize the complex effects of controlled pressure and exogenous ethanol environments on the metabolic regulatory network of Clostridium thermocellum. This approach will complement the genetic manipulation and adaptation of microorganisms for enhanced biobased production to meet the national and state's sustainable energy goals. A team of four experienced investigators (Chemical Engineering, Anaerobic Microbiology, Biomathematics, and Analytical Chemistry) will lead the execution of this project. A multidisciplinary approach allows a synergism in experimental design and analysis that would not be possible with a single investigator.