The Affinity of the Fucose‐binding Lectin From Lotus Tetragonolobus for Glycopeptides and Oligosaccharides Accumulating in Fucosidosis

The affinity of the fucose‐binding lectin from Lotus tetragonolobus for fuco‐oligosaccharides accumulating in the brain and other tissues of a patient with fucosidosis was studied by two methods: by inhibition of the co‐precipitation of the lectin with porcine stomach mucin and by one‐step affinity chromatography on a column of the lectin bound to Sepharose‐4B. Both methods indicated that the lectin had greater affinity for the disaccharide Fuc(α, 1‐6)GlcNAc than for either the main fucosidosis storage material in brain, a fuco‐dekasaccharide, or the heterogeneous fuco‐glycopeptide fractions obtained from normal human and rat brain glycoproteins. Our results suggest that the fucose residue linked α(1‐6) to the N ‐acetylglucosamine residue involved in the N ‐glycosidic linkage to asparagine is not available to the lectin in the intact N ‐glycosidic chains of normal brain glycopeptide fractions and that the lectin has poor affinity for the Fuc(α, 1‐3)Glc N Ac linkage in rat brain glycoproteins.