The Localization of Oligosaccharides in a Human IgM Protein

[摘要] Fab-like fragments were prepared by proteolysis of IgM (Dauphine) with papain, pepsin and trypsin. Analysis of these products by gas chromatography for their carbohydrate composition led to the localization of an oligosaccharide between the N-terminus of the molecule and the site of cleavage by trypsin at 37° which contained 1 mol of fucose, 3 mols of mannose, 2 mols each of galactose and glucosamine and 1 mol of sialic acid. A second oligosaccharide was located in the hinge region. It contained 6 to 7 mols of mannose, 2 mols of galactose and 3 mols of glucosamine. The Fc portion of the molecule contains one or more oligosaccharides consisting collectively of 1 mol of fucose, 10 or 11 mols of mannose, 1 mol of galactose, 5 mols of glucosamine and 3 mols of sialic acid per H chain.

[学科分类] 生物科学（综合）