ARS | Publication request: BACTERIA ENGINEERED FOR FUEL ETHANOL PRODUCTION: CURRENT STATUS

Submitted to: Applied Microbiology and Biotechnology
Publication Type: Review Article
Publication Acceptance Date: August 1, 2003
Publication Date: December 1, 2003
Citation: Dien, B.S., Cotta, M.A., Jeffries, T.W. 2003. Bacteria engineered for fuel ethanol production: current status. Applied Microbiology and Biotechnology. 63:258-266.

Technical Abstract: The lack of industrially suitable microorganisms for converting biomass into fuel ethanol has traditionally been cited as a major technical roadblock to developing a bioethanol industry. In the last two decades, numerous microorganisms have been engineered to selectively produce ethanol. Lignocellulosic biomass contains complex carbohydrates that necessitate utilizing microorganisms capable of fermenting sugars not fermentable by brewers yeast. The most significant of these is xylose. The greatest successes have been in the engineering of Gram-negative bacteria: Escherichia coli, Klebsiella oxytoca, and Zymomonas mobilis. E. coli and K. oxytoca are naturally able to use a wide-spectrum of sugars, and work has concentrated on engineering these strains to selectively produce ethanol. Z. mobilis produces ethanol at high yields, but only ferments glucose and fructose. Work on this organism has concentrated on introducing pathways for the fermentation of arabinose and xylose. The history of constructing these strains and current progress in refining them are detailed in this review.