Purification and characterization of a lectin from seeds of the winged bean, Psophocarpus tetragonolobus (L.)DC.
A lectin from seeds of the winged bean, Psophocarpus tetragonolobus (L.)DC, has been purified to homogeneity by affinity chromatography on a Bio-Gel lactobionate adsorbent. The lectin is rich in acidic amino acids, and after isoelectric focusing in polyacrylamide gel, appeared as a single band of pI5.5 The molecular weight of the lectin is 46 000 +/- 2000 as determined by analytical ultracentrifugation. Dodecyl sulfate gel electrophoresis detected a single type of subunit with a molecular weight of 29 000 +/- 3000. The lectin has specificity for receptors containing D-galactose and agglutinates trypsinized human red blood cells of all three ABO types. Of the tested inhibitors of hemagglutination caused by winged bean lectin, p-nitrophenyl-beta-D-galactoside was the most potent. Lactose was the most active oligosaccharide tested, and other oligosaccharides containing alpha-linked D-galactose were much less inhibitory.
D000596:Amino Acids / Q000032:analysis; D002241:Carbohydrates; D005690:Galactose; D006386:Hemagglutination Tests; D006801:Humans; D037102:Lectins / Q000302:isolation & purification; D046911:Macromolecular Substances; D008970:Molecular Weight; D013045:Species Specificity
D000596:Amino Acids; D002241:Carbohydrates; D037102:Lectins; D046911:Macromolecular Substances; D005690:Galactose