The crystal structure ofPterocarpus angolensislectin is determined in its ligand-free state, in complex with the fucosylated biantennary complex type decasaccharide NA2F, and in complex with a series of smaller oligosaccha-ride constituents of NA2F. These results together with thermodynamic binding data indicate that the complete oligosaccharide binding site of the lectin consists of five subsites allowing the specific recognition of the penta-saccharide GlcNAcb(1–2)Mana(1–3)[GlcNAcb(1–2)Mana(1–6)]Man. .
