title: Carbohydrate-binding specificity of Tetracarpidium conophorum lectin.
abstract: The carbohydrate-binding specificity of a novel plant lectin isolated from the seeds of Tetracarpidium conophorum (Nigerian walnut) has been studied by quantitative hapten inhibition assays and by determining the behavior of a number of oligosaccharides and glycopeptides on lectin-Sepharose affinity columns. The Tetracarpidium lectin shows preference for simple, unbranched oligosaccharides containing a terminal Gal beta 1----4GlNAc sequence over a Gal beta 1----3GlcNAc sequence and substitution by sialic acid or fucose of the terminal galactose residue, the subterminal N-acetylglucosamine or more distally located sugar residues of oligosaccharides reduce binding activity. Branched complex-type glycans containing either Gal beta 1----4GlcNAc or Gal beta 1----3GlcNAc termini bind with higher affinity than simpler oligosaccharides. The lectin shows highest affinity for a tri-antennary glycan carrying Gal beta 1----4GlcNAc substituents on C-2 and C-4 of Man alpha 1----3 and C-2 of Man alpha 1----6 core residues. Bi- and tri-glycans lacking this branching pattern bind more weakly. Tetra-antennary glycans and mono- and di-branched hybrid-type glycans also bind weakly to the immobilized lectin. Therefore, Tetracarpidium lectin complements the binding specificities of well-known lectins such as Datura stramonium agglutinin, Phaseolus vulgaris agglutinin, and lentil lectin and will be a useful additional tool for the identification and separation of complex-type glycans.
authors.affiliation: National Institute for Medical Research, Ridgeway, London, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Sato
authors.forename: T
authors.initials: T
authors.lastname: Animashaun
authors.forename: R C
authors.initials: RC
authors.lastname: Hughes
mesh_terms: D001212:Asialoglycoproteins; D050260:Carbohydrate Metabolism; D002846:Chromatography, Affinity; D060748:Fetuins; D006020:Glycopeptides / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D007118:Immunoassay; D037102:Lectins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009844:Oligosaccharides / Q000378:metabolism; D037121:Plant Lectins; D012639:Seeds; D013379:Substrate Specificity; D014197:Trees; D000509:alpha-Fetoproteins / Q000378:metabolism
chemical_list: D001212:Asialoglycoproteins; D060748:Fetuins; D006020:Glycopeptides; D006023:Glycoproteins; D037102:Lectins; D009844:Oligosaccharides; D037121:Plant Lectins; D000509:alpha-Fetoproteins; C017029:asialofetuin