(9b) Yeast Surface Display Mini-Cellulosme for Cellulose Hydrolysis

Cellulosomes are cellulolytic complexes found in many anaerobic microorganisms and have been shown to degrade cellulose efficiently. The major component of these macromolecule complexes is a structural scaffoldin consisting of repeating cohesin domains, which are docked individually with a cellulase tagged dockerin domain. The specific cohesin-dockerin interaction provides the mechanism for position-specific self-assembly. To emulate the success of a natural mechanism for efficient cellulose hydrolysis, a mini-cellulosome is assembled onto the yeast cell surface, enabling the ethanol-producing strain to utilize cellulose and concomitantly ferment it to ethanol. More importantly, by organizing these cellulases in an ordered structure, the enhanced synergy will increase the efficiency in hydrolysis, and thereby enhance ethanol production.