Researchers Engineer Novel β-glucosidase to Improve pH Stability

β-Glucosidase is a member of the biomass-degrading enzyme system and is vital in saccharification for biofuel production. In industrial practice, enzymes with high activity and great stability are always preferred. Hence, exploring natural enzymes and engineering superior mutants are approaches commonly used to improve saccharification.

Researchers from the Chinese Academy of Agricultural Sciences have identified a novel β-glucosidase, Bgl3A, from Talaromyces leycettanus JCM12802 and overexpressed it in Pichia pastoris GS115. The purified enzyme recovered exhibited outstanding enzymatic properties, including good thermostability, and high catalytic performance.

However, the wildtype Bgl3A only has a narrow pH stability of 4.0-5.0, which could limit its application. Researchers then modified the enzyme and removed potential O-glycosylation sites, improving its pH stability over a broader pH range (3.0-10.0). The enhanced mutants now show a much better application prospect with improved saccharification efficiency on cellulosic materials.