Alcohols for fuel:Biological energy to
usable energyBeth Papanek
Three main alcohols:
Methanol Ethanol Butanol
History of Ethanol
biofuelsdigest.com
Potential Yield
History of Butanol
Produced commercially starting in the 1920’s
Source: Hans Blaschek
Ethanol vs. Butanol
Wikipedia: “Ethanol” “isobutanol”
Comparison
Source: Hans Blaschek
Quick Biochem overview…
Saccharomyces cerevisiae
Butanol Metabolism
Source: Hans Blaschek
Problem: Preferential Hexose consumption
Source: bio.miami.edu
38-50% Cellulose, 15-30% Lignin, 23-32% Hemicellulose in cellulosic plants
Possible Improvements: Genetic Engineering
Saccharomyces cerevisiae Gene expression
for xylose uptake Increased xylose
transport
Clostridium beijerinckii Inhibitor tolerance Metabolic
constraints Electron flow
References
Ezeji, T., Qureshi, N., Blaschek, H. (2007) Bioproduction of butanol from biomass: from genes to bioreactors. Current Opinion in Biotechnology. 18: 220-227.
Gray, K., Zhao, L., Emptage, M. (2006) Bioethanol. Current Opinion in Chemical Biology. 10: 141-146.
Nevoigt, E. (2008) Progress in Metabolic Engineering of Saccharomyces cerevisiae. Microbioloby and Molecular Biology Reviews. 72: 379-412.