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Crystal structure of a GH1 β-glucosidase from Hamamotoa singularis.

ABSTRACT: 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.

SUBMITTER: Uehara R

PROVIDER: S-EPMC7454551 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Crystal structure of a GH1 β-glucosidase from Hamamotoa singularis.

Uehara Ryo R Iwamoto Riki R Aoki Sayaka S Yoshizawa Takuya T Takano Kazufumi K Matsumura Hiroyoshi H Tanaka Shun-Ichi SI

Protein science : a publication of the Protein Society 20200806 9

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 elemen ...[more]

PMID: 32713015

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