CLOSTRIDIUM THERMOCELLUM STRAINS FOR ENHANCED ETHANOL PRODUCTION AND METHOD OF THEIR USE

摘要

Clostridium thermocellum is a thermophilic anaerobic bacterium that specializes in the rapid solubilization and fermentation of crystalline cellulose to products that include ethanol. C. thermocellum deletion mutants have been constructed to eliminate pyruvate-formate lyase (pfl) and hydrogenases activities. C. thermocellum Apfl no longer synthesizes formate. The pfl mutants make less acetate than the parental strain. The mutant that does not express one of the maturation proteins required for production of functional hydrogenases in C. thermocellum has reduced acetate production as compared to normal strains.