Design to Data for Mutant of β-Glucosidase B from Paenibacillus polymyxa: G23S

O'Donnell, A.; Abbas, G.

doi:10.64898/2026.04.27.721118

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bioRxiv · 10.64898/2026.04.27.721118

Design to Data for Mutant of β-Glucosidase B from Paenibacillus polymyxa: G23S

O'Donnell, A.·Abbas, G.

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Abstract

{beta}-glucosidase (BglB) from Paenibacillus polymyxa was mutated (G23S, Rosetta/Foldit numbering; G26S, conventional numbering) to assess structural and functional changes. Foldit modeling and prior Design 2 Data (D2D) database results led us to hypothesize that this mutation would increase substrate binding affinity and catalytic efficiency, with a moderate reduction in thermal stability. The mutant protein was expressed, purified, and analyzed using kinetics and thermal stability assays. Relative to the wild-type (WT), G23S exhibited a similar binding affinity (similar Km), an approximately 2-fold increase in turnover number (kcat) and catalytic efficiency (kcat/Km), an almost 14-fold increase in maximum reaction velocity (Vmax) and a slight decrease in thermostability (T50). The results largely support the hypothesis, indicating that changes in residue 23 can enhance catalytic power while minimally compromising stability.

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O'Donnell, A., Abbas, G.. 2026-04-30. Design to Data for Mutant of β-Glucosidase B from Paenibacillus polymyxa: G23S. https://doi.org/10.64898/2026.04.27.721118

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