Purification of the glycoprotein lectin from the broad bean (Vicia faba) and a comparison of its properties with lectins of similar specificity.
1. The lectin from the broad bean (Vicia faba) was purified by affinity chromatography by using 3-O-methylglucosamine covalently attached through the amino group to CH-Sepharose (an omega-hexanoic acid derivative of agarose). Its composition and the nature of its subunits were compared with concanavalin A and the lectins from pea and lentil. 2. Unlike the other three lectins, broad-bean lectin is a glycoprotein; a glycopeptide containing glucosamine and mannose was isolated from a proteolytic digest. 3. The mol.wt. is about 47500; the glycoprotein consists of two apprently identical subunits, held together by non-covalent forces. Fragments of the subunits, similar to those found in concanavalin A and soya-bean agglutinin, were found in active preparations. 4. Broad-bean lectin was compared with concanavalin A and the lectins from pea and lentil in an investigation of the inhibition of their action by a number of monosaccharides, methyl ethers of monosaccharides, disaccharides and glycopeptides. The most striking differences concern 3-O-substituted monosaccharides, which are strong inhibitors of the action of broad-bean, pea and lentil lectins but not of the action of concanavalin A. There is, however, no strong inhibition of the action of these lectins by 3-Olinked disaccharides.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002241:Carbohydrates / Q000032:analysis / Q000494:pharmacology; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D003208:Concanavalin A / Q000032:analysis / Q000037:antagonists & inhibitors; D004591:Electrophoresis, Polyacrylamide Gel; D006020:Glycopeptides / Q000302:isolation & purification; D006168:Guinea Pigs; D006386:Hemagglutination Tests; D006801:Humans; D037102:Lectins / Q000302:isolation & purification*; D008970:Molecular Weight; D010447:Peptide Hydrolases; D037121:Plant Lectins; D010944:Plants / Q000032:analysis*; D011817:Rabbits
D000596:Amino Acids; D002241:Carbohydrates; D006020:Glycopeptides; D037102:Lectins; D037121:Plant Lectins; D003208:Concanavalin A; D010447:Peptide Hydrolases