Metabolomic Analysis of Butanol Production Under Stress

Butanol is a renewable drop-in fuel and can work with current vehicles designed for use with gasoline without modification. It has higher energy content and lower vapor pressure when compared with ethanol. Butanol can be produced by Clostridium fermentation from biomass feedstocks. The products composition and productivity of Clostridium fermentation are determined by nutrients, primary and secondary metabolites and environmental factors. Combination of metabolomes with transcriptomes will provide deeper understanding of viability and productivity of Clostridium fermentation. The objective of this study is to identify metabolites and other stress compounds associated with Clostridium viability and productivity. The working hypothesis is that microbial metabolites are regulated by life cycle changes and environmental factor during fermentation. The approach is to use QToF-LC/MS and 1H NMR (Fig.1) to analyze all the extracellular and intercellular metabolites of engineered and wild-type strains under various stress. 

It is expected that metabolomics analysis will reveal an orderly progression of changes in intracellular metabolites over the time course, and also the changes in intracellular metabolites associated to fermentation variability and longevity. It is expected that the levels of amino acids, upper glycolytic intermediates, and pentose phosphate pathway compounds changed in acidogenesis and solventogenesis will be determined. The levels of butyryl-phosphate and acetyl-phosphate in acidogenesis and solventogenesis will be revealed. ATP, NADH, butyryl-CoA, diphosphates, nucleosides and bases will be determined. The protégé students will work on metabolites analysis with hand-on experiences in sample preparation, QToF LC/MS analysis, microbial fermentation and 1H and 2D NMR analysis.