Isolation of a collagen fraction from the body-wall glycoproteins of the leech (Hirudo medicinalis), and characterization of its carbohydrate-amino acid portion

Fractionation of the leech (Hirudo medicinalis) body-wall glycoproteins yielded a collagen fraction containing only d-glucose and d-galactose as its carbohydrate constituents. Digestion of the collagen with trypsin and pronase, and alkaline degradation of the resulting glycopeptides, gave a product that contained a disaccharide linked to hydroxylysine. Mild, acid hydrolysis of the N-acetylated glycopeptides yielded a disaccharide consisting of a d-glucose and a d-galactose residue. Various chemical and enzymic reactions of the disaccharide, the glycosyloxylysine, and the glycopeptide fraction indicated that the disaccharide is 2-O-α-d-glucopyranosyl-d-galactose, and that this is β-glycosidically linked to O-5 of the hydroxylysine residue in the collagen.