Crystal structure of a GH1 β-glucosidase from Hamamotoa singularis

Protein Sci. 2020 Sep;29(9):2000-2008. doi: 10.1002/pro.3916. Epub 2020 Aug 6.


A GH1 β-glucosidase from the fungus Hamamotoa singularis (HsBglA) has high transgalactosylation activity and efficiently converts lactose to galactooligosaccharides. Consequently, HsBglA is among the most widely used enzymes for industrial galactooligosaccharide production. Here, we present the first crystal structures of HsBglA with and without 4'-galactosyllactose, a tri-galactooligosaccharide, at 3.0 and 2.1 Å resolutions, respectively. These structures reveal details of the structural elements that define the catalytic activity and substrate binding of HsBglA, and provide a possible interpretation for its high catalytic potency for transgalactosylation reaction.

Keywords: Hamamotoa singularis; crystal structure; galactooligosaccharide; transgalactosylation; β-galactosidase; β-glucosidase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Basidiomycota / enzymology*
  • Crystallography, X-Ray
  • Fungal Proteins / chemistry*
  • Protein Domains
  • beta-Glucosidase / chemistry*


  • Fungal Proteins
  • beta-Glucosidase

Supplementary concepts

  • Hamamotoa singularis