Lacto-N-biosidase

Lacto-N-biosidase
Identifiers
EC number	3.2.1.140
CAS number	146359-52-6
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

Lacto-N-biosidase (EC 3.2.1.140) is an enzyme with systematic name oligosaccharide lacto-N-biosylhydrolase.^[1][2] This enzyme catalyses the following chemical reaction

(1) beta-D-Gal-(1->3)-beta-D-GlcNAc-(1->3)-beta-D-Gal-(1->4)-D-Glc + H₂O $\rightleftharpoons$ beta-D-Gal-(1->3)-D-GlcNAc + beta-D-Gal-(1->4)-D-Glc

(2) lacto-N-tetraose + H₂O $\rightleftharpoons$ lacto-N-biose + lactose

The enzyme from Streptomyces specifically hydrolyses the terminal lacto-N-biosyl residue (beta-D-Gal-(1->3)-D-GlcNAc) from the non-reducing end of oligosaccharides with the structure beta-D-Gal-(1->3)-beta-D-GlcNAc-(1->3)-beta-D-Gal-(1->R).

References

1. Sano, M., Hayakawa, K., Kato, I. (1992). "An enzyme releasing lacto-N-biose from oligosaccharides". Proc. Natl. Acad. Sci. USA 89: 8512–8516. doi:10.1073/pnas.89.18.8512. PMID 1528855.
2. Sano, M., Hayakawa, K., Kato, I. (1993). "Purification and characterization of an enzyme releasing lacto-N-biose from oligosaccharides with type 1 chain". J. Biol. Chem. 268: 18560–18566. PMID 7689556.

External links

• Lacto-N-biosidase at the US National Library of Medicine Medical Subject Headings (MeSH)