Differential binding properties of Gal/GalNAc specific lectins available for characterization of glycoreceptors

Differentiating the binding properties of applied leclins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAcα1→Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAcα1→3GalNAc), Forssman specific disaccharide - Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAcα1→3Gal), blood group A specific disaccharide -Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A₄ (VVL-A₄), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAcα1→Ser (Thr) of the protein core) - Vicia villosa B₄ (VVL-B₄), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Galβ1→3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(Tα), T antigen or the disaccharides at the terminal nonreducing end of gangliosides(Tβ) - Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonicá (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Galβ1→3(4)GlcNAc) - the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage - Ricinus communis agglutinin (RCA₁), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Galα1→3Gal), human blood group B specific disaccharide -Griffonia(Bandeiraea) simplicifolia B₄ (GSI-B₄). ('7) E (Galα1→4Gal), receptors for pathogenic E. coli agglutinin, Shiga toxin and Mistletoe toxic lectin-I (ML-I) and abrin-a.