Glycoproteins blood group determinants

The possible role that the lysine residues, N-terminal amino acid residues, and carbohydrate residues may play in the display of the MN blood-group determinants by glycophorins A, A, and has been investigated. Assuming that the N-terminal amino acid in each of these glycoproteins plays a prominent role in the display of the MN blood-group determinant, labels were placed on the N-terminal amino acid residues of the glycoproteins. 

Figure 14.2 Representative oligosaccharide structures found on mammalian glycoproteins and glycolipids. The complex oligosaccharides may be bi-, tri-, or tetra-antennary the branches may be more or less elongated with 1—>4 linked lactosamine units, and they may or may not be sialylated. The SLex, Lea, and Leb structures represent the different blood group determinants often present on lipids, and the elongated core 2 structure is a mucin-type glycosylation. Proteoglycans have a common core to which a variety of linear acidic polysaccharides are attached.

L-Fucose may be present in O- and N-glycosylic chains of glycoproteins.85 Polylactosamine chains in O- or N-linked glycans of glycoproteins, or in gly-cosphingolipids, may be modified by attachment of fucose residues, giving rise to blood-group determinants.205... 

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