(440c) Overexpression of Endoglucanase Enables Bacillus Subtilis to Grow On Cellulose as the Sole Carbon Source in Defined Media

Consolidated bioprocessing (CBP) is a low-cost cellulosic biomass processing by integrating cellulase production, cellulose hydrolysis, and sugar fermentation into a single step. Although significant efforts have been made to create recombinant cellulolytic microorganisms, recombinant cellulolytic microorganism that can produce sufficient secretory active cellulases, hydrolyze cellulose, and utilize soluble sugars for supporting cell growth and cellulase synthesis without organic nutrients is not available. Here we demonstrated that over-expression of Bacillus subtilis endoglucanase (BsCel5) by more than 30-fold enables non-cellulose-utilizing Bacillus subtilis strains (168, WB800, and IH1640) to grow on cellulose and pretreated lignocellulosic biomass as the sole carbon source without addition of costly organic nutrients. Secretory active endoglucanases account for up to 6% of total cellular protein weight of the recombinant Bacillus strains. The recombinant cellulolytic Bacillus microorganisms would be an aerobic CBP platform for low-cost production of advanced biofuels or biobased products.