earticle

영어

Consolidated bioprocessing (CBP) of cellulosic biomass to ethanol combines the steps including cellulose production, saccharification, and fermentation into one step. Although this process is considered as the most efficient way to reduce the production cost of ethanol from cellulosic biomass, the microorganisms enabling the CBP are still under development. We develop cellulolytic yeast strains for ethanol production by imitating the cellulosome complex system of the cellulolytic bacterium, Clostridium thermocellum. The protein that mediates the assembly of the C. thermocellum cellulosome is the scaffoldin component that contains cellulose-binding module (CBM) and cohesin domains which interact with the enzyme-borne dockerin domains. Here, a modified scaffoldin including CBM and cohesin domains is fused to Aga2 and displayed on the surface of Saccharomyces cerevisiae. Various cellulases including dockerin domain are secreted from separate yeast cells and assembled to the scaffoldin successfully by using mixed yeast cell culture. This result represents the possible reconstitution of cellulosome structure and production of cellulosic ethanol without additional cellulase supply.