Engineered E.coli transforms switchgrass to fuels

In the growing demand of fuels, scientists had already started looking for the alternatives which would be environment friendly and economic to produce. This study is one such approach to reduce the costs of advanced biofuel production from cellulosic biomass to engineer a single microorganism to both digest plant biomass and produce hydrocarbons that have the properties of petrochemical fuels. Researchers from Joint BioEnergy Institute (JBEI), University of California have engineered an Escherichia coli that can digest switchgrass biomass pretreated with ionic liquid and synthesize its sugars into all three of those transportation fuels. The engineered strains express cellulase, xylanase, beta-glucosidase, and xylobiosidase enzymes under control of native E. coli promoters selected to optimize growth on model cellulosic and hemicellulosic substrates. These cellulolytic and hemicellulolytic strains of E. coli, which can be combined as co-cultures on a sample of switchgrass, were further engineered with three metabolic pathways that enabled the E. coli to produce fuel substitute or precursor molecules suitable for gasoline, diesel and jet engines.

In conclusion, this study mainly cuts down the additional use of enzymes which used to be very cost effective. The ionic liquid pretreatment of plant biomass with appropriate regulation and tractability opens the door for an economical production of advanced fuels. Further improvement in the genetic stability of modified organism and its suitability for industrial scale fermentation would be the next step to increase the yields of the fuels.

Link to this post: http://www.pnas.org/content/early/2011/11/21/1106958108.full.pdf+html