Psophocarpus tetragonolobus (Winged bean) Lectin (PTL/PTA II- GalNAc)
Psophocarpus tetragonolobus lectin (PTA/PTL II, psophocarpin B1, a storage protein with chymotrypsin inhibitory activity), is isolated from winged bean seeds and purified by affinity chromatography. The seed contains two lectins in which PTL II is the acidic of the two, with an isoelectric point of pH 5.5 and a molecular weight of around 54, 000. PTL II has a carbohydrate specificity towards D-Galactose and GalNAc, with eluting sugar D-Galactose.This lectin agglutinates trypsinized and desialized erythrocytes of all three blood group types (A, B, and O). Nonpolar interactions play an important role in stabilization of the lectin-sugar complex. Projection of 1, 3 linked Gal/GalNAc leads to steric hindrance and prevents the binding of blood group A and B reactive sugars.The unique specificity of PTL II makes it to be useful in isolation and characterization of terminally monofucosylated H-reactive oligosaccharides from those that are difucosylated or internally fucosylated. See other PTL II conjugates.This product comes in a lyophilized form and is stored at -20° C.