ABSTRACT
β-Glucosidases (BGLs) are among the most abundant and widely studied glycosyl hydrolases and are industrially relevant as important “blend in” enzymes for biomass hydrolyzing cellulase cocktails. Although there are multiple sources of the enzyme, fungals are known to be the high-titre industrial producers of BGLs. The transglycosylation potential of at least some BGLs is relevant for the generation of inducers of the cellulolytic enzymes in fungi. BGLs act as the rate-limiting enzyme in cellulose hydrolysis, due to their feedback inhibition by their own product: glucose. Insights into their structure and mechanism of action, the potent producers of BGLs, the importance of glucose tolerance in BGLs, their properties, and the proposed molecular interventions for enhancing BGL production and their secretion in fungi are discussed. Formulations of efficient biomass hydrolyzing enzymes through supplementation of heterologous BGLs with rapid turnover and/or glucose tolerance into cellulase preparations for enhancing biomass hydrolysis in biorefineries are described along with strategies for developing sustainable in-house production of enzymes.
