Reaction: [(1→2)-β-D-glucosyl]n + H2O = sophorose + [(1→2)-β-D-glucosyl]n-2
Glossary: sophorose = β-D-glucopyranosyl-(1→2)-D-glucopyranose
Systematic name: exo (1→2)-β-D-glucooligosaccharide sophorohydrolase (non-reducing end)
Comments: The enzyme, characterized from the bacterium Parabacteroides distasonis, specifically hydrolyses (1→2)-β-D-glucooligosaccharides to sophorose. The best substrates are the tetra- and pentasaccharides. The enzyme is not able to cleave the trisaccharide, and activity with longer linear (1→2)-β-D-glucans is quite low. This enzyme acts in exo mode and is not able to hydrolyse cyclic (1→2)-β-D-glucans.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
1. Shimizu, H., Nakajima, M., Miyanaga, A., Takahashi, Y., Tanaka, N., Kobayashi, K., Sugimoto, N., Nakai, H. and Taguchi, H. Characterization and structural analysis of a novel exo-type enzyme acting on β-1,2-glucooligosaccharides from Parabacteroides distasonis. Biochemistry 57 (2018) 3849-3860. [PMID: 29763309]