Ezeji Awarded NSF Grant

Dr. Thaddeus Ezeji, associate professor in the Department of Animal Sciences, has been awarded a continuing grant by the National Science Foundation. The $95,779.00 grant is for Ezeji's work as primary investigator on "Developing second-generation hyper-producers of butanol from biomass by activating dormant pathways." The abstract for the grant is below.

Renewable production of fuels and chemicals is growing. One strategy involves producing fuels and chemicals using microbes. Unfortunately, these chemicals often exert toxic effects on microorganisms at high concentrations. Butanol is one example of this. It has excellent properties as a transportation fuel. At high concentrations, it poisons the microbes that produce it. The central goal of the project is to enhance the ability of butanol-producing bacteria to withstand high concentrations of butanol. Undergraduate and graduate students will receive hands-on research training and mentorship. International outreach will focus on delivering a course on biofuels production in Nigeria. These experiences should prepare the students for successful careers in a global workforce.

A major challenge for bioconversion of lignocellulosic biomass hydrolysates (LBH) stems from the toxicity posed by microbial inhibitory compounds (MICs) generated during metabolic processing of LBH. The long-term objective is to develop a rational approach for engineering inhibitory compound tolerance in Clostridium beijerinckii. A two-pronged strategy will be pursued. Interdependent utilization of two different waste products, glycerol and LBH, for improved solvent generation in the presence of MICs will be characterized. Also, DNA repair competence of C. beijerinckii will be increased. We hypothesize that cellular reductants [NAD(P)H] needed for detoxification of MICs and for butanol synthesis can be generated by activating a dormant pentose phosphate pathway coupled with glycerol utilization. This proposal seeks to repurpose existing pathways in C. beijerinckii to overcome metabolic hurdles. By combining metabolic engineering and reverse genetics, the project aims to uncover new determinants for butanol production by C. beijerinckii, and generate a broader framework for better microbial conversion of renewable feedstock to fuels and chemicals.