title: Purification and characterization of two lectins from calllus of Helianthus tuberosus.
abstract: Two lectins were purified from Helianthus tuberosus callus by maltose affinity chromatography and subsequent preparative electrophoresis. The lectins were designated HTA I and HTA II and their molecular masses were about 34 kDa by gel-filtration chromatography. A single band of 17 kDa and bands of 17 kDa and 18 kDa were detected after SDS-PAGE of HTA I and HTA II, respectively, indicating that HTA I is a homodimer while HTA II is a heterodimer. The amino acid compositions of the two lectins were very similar; they were rich in glycine residues, lacking detectable amounts of methionine, cysteine, and histidine. A hapten-inhibition assay showed that HTA I and HTA II had identical saccharide-binding specificity to the extent tested and belonged to the group of so-called mannose/glucose-binding lectins. They had high affinity for alpha-linked manno-oligosaccharides. Each HTA completely lost its hemagglutinating activity at pH 5.0, as a result of its dissociation to monomers, but it did not lose its ability to bind to oligosaccharides.
authors.affiliation: Hokkaido Food Processing Research Center, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Nakagawa
authors.forename: D
authors.initials: D
authors.lastname: Yasokawa
authors.forename: T
authors.initials: T
authors.lastname: Ikeda
authors.forename: K
authors.initials: K
authors.lastname: Nagashima
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002240:Carbohydrate Sequence; D004912:Erythrocytes / Q000187:drug effects; D006368:Helianthus / Q000737:chemistry*; D006386:Hemagglutination Tests; D037102:Lectins / Q000032:analysis / Q000302:isolation & purification* / Q000494:pharmacology; D008970:Molecular Weight; D009005:Monosaccharides / Q000378:metabolism; D010936:Plant Extracts / Q000032:analysis / Q000302:isolation & purification* / Q000494:pharmacology; D037121:Plant Lectins; D011817:Rabbits; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D037102:Lectins; D009005:Monosaccharides; D010936:Plant Extracts; D037121:Plant Lectins