Related lectins from snowdrop and maize differ in their carbohydrate-binding specificity

Abstract

Searches in an EST database from maize revealed the expression of a protein related to the Galanthus nivalis (GNA) agglutinin, referred to as GNAmaize. Heterologous expression of GNAmaize in Pichia pastoris allowed characterisation of the first nucleocytoplasmic GNA homolog from plants. GNAmaize is a tetrameric protein which shares 64% sequence similarity with GNA. Glycan microarray analyses revealed important differences in the specificity. Unlike GNA, which binds strongly to high-mannose N-glycans, the lectin from maize reacts almost exclusively with more complex glycans. Interestingly, GNAmaize prefers complex glycans containing β1-2 GlcNAc residues. The obvious difference in carbohydrate-binding properties is accompanied by a 100-fold reduced anti-HIV activity. Although the sequences of GNA and GNAmaize are clearly related they show only 28% sequence identity. Our results indicate that gene divergence within the family of GNA-related lectins leads to changes in carbohydrate binding specificity, as shown on N-glycan arrays.

High Mannose-binding Lectin with Preference for the Cluster of α1–2-Mannose from the Green Alga Boodlea coacta Is a Potent Entry Inhibitor of HIV-1 and Influenza Viruses

“…The legume lectin family is another large group of plant lectins that includes the various high mannose-binding lectins (3). Importantly, some of these high mannose-binding plant lectins exhibit a strong anti-HIV activity, but others are weak or completely inactive (4,5). Such different biological activities virtually depend on the diverse carbohydrate specificities of these plant lectins.…”

Purification, characterization and molecular cloning of a monocot mannose-binding lectin from Remusatia vivipara with nematicidal activity

“…Recent report on the carbohydrate binding specificities of Galanthus nivalis agglutinin (GNA) and GNA like the lectin from Zea mays (GNA maize ) was determined by glycan array analysis which demonstrated that GNA recognizes mannose weakly, but strongly binds to high mannose type glycans. GNA maize , unlike GNA binds exclusively to high mannose type and complex N-glycans [33]. Considering the exclusive carbohydrate specificity of these lectins towards high mannose type N-glycans commonly occurring in animal glycoproteins, it is speculated that these plant proteins are evolved for defense purpose [13].…”

Variability among TSH Measurements Can Be Reduced by Combining a Glycoengineered Calibrator to Epitope-Defined Immunoassays

“…All TSHs showed different profiles. pitTSH showed a higher ConA signal, most probably due to a high content in biantennary structures [5,[28][29][30] , and elevated core fucosylation (LCA), but very low level of galactose (ECL), α2,3-(WGA) and α2,6-sialic acid (SNA) because its glycans terminate in sulfated-GalNAc [5,10] ( fig. 2 a).…”

“…Again, most group B assays showed quite a superior binding capacity, with the highest signals being observed with B2 and B3 for both calibrations. [28] , Galanthus nivalis lectin (GNL) binds hybrid and high-mannose glycans [29] , Lens culinaris agglutinin (LCA) recognizes preferentially core-α1,6-fucosylated glycans [30] , Erythrina cristagalli lectin (ECL) binds terminal β1,4-galactose of complex glycans [30] , wheat germ agglutinin (WGA) binds α2,3-sialic acids [30] , and SNA binds α2,6-sialic acids [30] . Error bars indicate standard deviation.…”