Improved beta-glucosidase enzymes for increased biomass saccharification

Conversion of cellobiose to glucose by β-glucosidase (BG) is the last step in enzymatic hydrolysis of cellulose for glucose production, where cellobiose is known to be a strong inhibitor of both endoglucanases and exoglucanases.  Hence, BG activity is a key component of commercial enzyme cocktails.  However, BG activity in some enzyme cocktails may not be sufficient to achieve the maximum sugar yields and additionally, some of the activity may be lost or inhibited during the course of saccharification.  Strategies for enhancement of base enzyme cocktails by BG have been technically successful and applied by various enzyme producers.  We isolated polynucleotides that encode polypeptides having improved BG activities.  Our genetically modified BG has shown enhanced activity and improved kinetic properties versus benchmark enzymes.  Data will be presented demonstrating improved performance.