title: Isolation and characterization of a lectin from tulip bulbs, Tulipa gesneriana.
abstract: A lectin, which agglutinated specifically the yeast cells of the Saccharomyces genus, was isolated from tulip bulbs (Tulipa gesneriana) using affinity chromatography on mannan-Sepharose 4B. Its relative molecular mass was determined by gel filtration to be approximately 67,000. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, a relative molecular mass of 17,000 was obtained, suggesting that the lectin is a tetramer. Binding studies performed with iodinated lectin indicated that Saccharomyces cerevisiae cells contained approximately 5.7 X 10(6) binding sites per cell, whereas little binding was observed with yeasts other than the Saccharomyces genus, bacteria and animal erythrocytes. D-Mannose, D-mannose 6-phosphate, L-fucose and L-fucosylamine were potent inhibitors of the lectin binding to S. cerevisiae cells, while, D-glucose, D-galactose and D-mannosamine were inactive, indicating that hydroxyl group at C-2 of D-mannose was essential for the lectin binding. Furthermore, inhibition experiments, using various manno-oligosaccharides, suggested that the lectin recognized (1----6)-linked manno-oligosaccharide units larger than mannobiose.
mesh_terms: D000371:Agglutination; D000596:Amino Acids / Q000032:analysis; D002241:Carbohydrates / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D006023:Glycoproteins / Q000494:pharmacology; D007457:Iodine Radioisotopes; D007700:Kinetics; D037102:Lectins / Q000302:isolation & purification* / Q000378:metabolism; D008351:Mannans / Q000494:pharmacology; D008970:Molecular Weight; D037121:Plant Lectins; D010944:Plants / Q000032:analysis*
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D006023:Glycoproteins; D007457:Iodine Radioisotopes; D037102:Lectins; D008351:Mannans; D037121:Plant Lectins; D003208:Concanavalin A