Figure 6. Structures of the pyridylaminated-oligosaccharides liberated from the 32-kDa enamelin by glycopeptidase F digestion (Yamakoshi, 1995). Asn²⁴⁵ uses all five of the biantennary types shown on the right. Asn²⁵² uses the top two biantennary types. Asn²⁶⁴ uses the three triantennary types shown on the left (Yamakoshi et al., 1998). Key: fucose, F; galactose, G; N-acetylglucosamine, GN; mannose, M; N-acetylneuraminic acid, S. Diagram showing the position of the 32-kDa enamelin cleavage product in the 186-kDa secreted enamelin protein and the positions of the two phosphorylations (P) and glycosylations (Gly).