Anaerobic respiration in engineered Escherichia coli with an internal electron acceptor to produce fuel ethanol.
Environmental concerns and unease with U.S. dependence on foreign oil have renewed interest in converting biomass into fuel ethanol. The volume of plant matter available makes lignocellulose conversion to ethanol desirable, although no one isolated organism has been shown to break bonds in lignocellulose and efficiently metabolize resulting sugars into one product. This work reviews directed engineering coupled with metabolic evolution resulting in microbial biocatalysts that produce up to 45 g L(-1) ethanol in 48 hours in a simple mineral salts medium and that convert various compounds of lignocellulosic materials to ethanol. Mutations contributing to ethanologenesis are discussed along with adding enzymatic capabilities to existing biocatalysts in order to decrease the commercial enzymes required to reduce plant matter into fermentable sugars.
Peterson
Joy Doran
JD
Microbiology Department, University of Georgia, Athens, GA 30602, USA. jpeterso@uga.edu
Ingram
Lonnie O
LO
D000383:Agriculture; D000693:Anaerobiosis; D004579:Electron Transport; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005648:Fuel Oils; D005818:Genetic Engineering; D006601:Hexoses / Q000378:metabolism; D010429:Pentoses / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism
D005648:Fuel Oils; D006601:Hexoses; D010429:Pentoses; D011134:Polysaccharides; D000431:Ethanol; C007916:hemicellulose