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Blood-group-substance endo-1,4-β-galactosidase (EC3.2.1.102, endo-β-galactosidase, blood-group-substance 1,4-β-D-galactanohydrolase) is an enzyme with systematic nameblood-group-substance 4-β-D-galactanohydrolase. It catalyses endohydrolysis of (1→4)-β-D-galactosidic linkages in blood group A and B substances.
It hydrolyses the 1,4-β-D-galactosyl linkages adjacent to a 1,3-α-D-galactosyl or N-acetylgalactosaminyl residues and a 1,2-α-D-fucosyl residue.
References
Fukuda MN, Matsumura G (October 1976). "Endo-β-galactosidase of Escherichia freundii. Purification and endoglycosidic action on keratan sulfates, oligosaccharides, and blood group active glycoprotein". The Journal of Biological Chemistry. 251 (20): 6218–25. PMID135762.
Nakazawa K, Suzuki S (February 1975). "Purification of Keratan Sulfate-endogalactosidase and its action on keratan sulfates of different origin". The Journal of Biological Chemistry. 250 (3): 912–7. PMID234443.
Takasaki S, Kobata A (June 1976). "Purification and characterization of an endo-β-galactosidase produced by Diplococcus pneumoniae". The Journal of Biological Chemistry. 251 (12): 3603–9. PMID6459.