6JFP

Crystal structure of the beta-glucosidase Bgl15

Summary for 6JFP

• Entry DOI: 10.2210/pdb6jfp/pdb
• Descriptor: beta-glucosidase 15, beta-D-glucopyranose (3 entities in total)
• Functional Keywords: beta-glucosidase, glucose-tolerance, thermostability, directed evolution, sugar binding protein
• Biological source: uncultured bacterium
• Total number of polymer chains: 2
• Total formula weight: 105983.98

Authors

Xie, W.,Chen, R. (deposition date: 2019-02-11, release date: 2020-02-12, Last modification date: 2023-11-22)

Primary citation

Cao, L.,Chen, R.,Huang, X.,Li, S.,Zhang, S.,Yang, X.,Qin, Z.,Kong, W.,Xie, W.,Liu, Y.
Engineering of beta-Glucosidase Bgl15 with Simultaneously Enhanced Glucose Tolerance and Thermostability To Improve Its Performance in High-Solid Cellulose Hydrolysis.
J.Agric.Food Chem., 68:5391-5401, 2020

PubMed Abstract: In this study, a Petri-dish-based double-layer high-throughput screening method was established to improve glucose tolerance of β-glucosidase Bgl15. Two beneficial mutations were identified, and the joint mutant 2R1 improved the half-maximal inhibitory concentration of glucose from 0.04 to 2.1 M. The crystal structure of 2R1 was subsequently determined at 2.7 Å. Structure analysis revealed that enhancement of glucose tolerance may be due to improved transglycosylation activity made possible by a hydrophobic binding site for glucose as an acceptor and more stringent control of a putative water channel. To further ameliorate the application potential of the enzyme, it was engineered to increase the half-life at 50 °C from 0.8 h (Bgl15) to 180 h (mutant 5R1). Furthermore, supplementation of 5R1 to the cellulase cocktail significantly improved glucose production from pretreated sugar cane bagasse by 38%. Consequently, this study provided an efficient approach to enhance glucose tolerance and generated a promising catalyst for cellulose saccharification.

PubMed: 32338906
DOI: 10.1021/acs.jafc.0c01817

Experimental method

X-RAY DIFFRACTION (2.7 Å)