Engineering a cellulolytic escherichia coli towards consolidated bioprocessing

Abstract

The current energy crisis is exponentially growing and widening the chasm between demand and supply. Biofuels such as ethanol not only provide greener alternatives to fossil fuels but have been shown to reduce emissions from vehicles, improving air etc. Biofuel production from sources such as cellulose is believed to be more sustainable due to its low cost, vast availability in nature and sources such as industrial plant waste can be put to good use. However, due to the absence of a low-cost technology to overcome its recalcitrance, a concept called Consolidated Bioprocessing (CBP) has been put forward which proposes to integrate the production of saccharolytic enzymes, hydrolysis of the carbohydrate components to sugar molecules, and the fermentation of hexose and pentose sugars to biofuels into a single process. The present study involves development of cellulolytic E. coli strains towards cellodextrin assimilation by employing an energy-saving strategy in cellulose metabolism through the phosphorolytic cleavage of cellodextrin mixture produced as cellulosic degradation products.