Reaction: lacto-N-neotetraose + H2O = N-acetyllactosamine + lactose
Glossary: lacto-N-neotetraose = β-D-Gal-(1→4)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc
N-acetyllactosamine = β-D-Gal-(1→4)-D-GlcNAc
Systematic name: oligosaccharide exo β-(1,3)-N-acetyllactosamine hydrolase (non-reducing end)
Comments: The enzyme, characterized from several bacterial species, hydrolyses the terminal N-acetyllactosamine residue (β-D-Gal-(1→4)-D-GlcNAc) from the non-reducing end of oligosaccharides with the structure β-D-Gal (1→4)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→R). The enzyme also catalyses the activity of EC 3.2.1.140, lacto-N-biosidase, and is not active on oligosaccharides with a terminal GlcNAc residue.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Vuillemin, M., Muschiol, J., Zhang, Y., Holck, J., Barrett, K., Morth, J.P., Meyer, A.S. and Zeuner, B. Discovery of lacto-N-biosidases and a novel N-acetyllactosaminidase activity in the CAZy family GH20: functional diversity and structural insights. Chembiochem (2024) e202400710. [PMID: 39239753]