title: The lectin riddle: glycoproteins fractionated from complex mixtures have similar glycomic profiles.
abstract: One common method used for analyzing the glycoproteome is chromatography using multiple lectins that display different affinities toward oligosaccharide structures. Much has been done to determine lectin affinity using standard glycoproteins with known glycosylation; however, a knowledge of the selectivity and specificity of lectins exposed to complex mixtures of proteins is required if they are to be used as a means of studying the glycoproteome. In the present study, three lectins (Concanavalin A, Jacalin, and Wheat Germ Agglutinin) were used to fractionate glycoproteins from two different complex environments: (1) cell membranes and (2) plasma. Reproducible enrichment of glycoproteins from these samples has been shown to result from the combined use of these lectins. However, the global glycan profiles of the released N- and O-linked oligosaccharides from the glycoproteins retained by the lectins, and from those glycoproteins that did not bind, using both these complex samples, were found to be very similar. That is, although the lectins selectively and reproducibly retained some glycoproteins, other proteins with the same attached oligosaccharide structures did not bind. Some small N- and O-glycan differences were observed in the bound fractions but there was little absolute specificity toward individual oligosaccharide structures known to have high affinity to these lectins. These data indicate that lectins are useful for fractionating glycoproteins from complex mixtures, but that the overall glycoproteome is not isolated by this approach.
authors: Department of Chemistry and Biomolecular Sciences, Macquarie University, Australia.
authors: Albert
authors: A
authors: Lee
authors: Miyako
authors: M
authors: Nakano
authors: Marina
authors: M
authors: Hincapie
authors: Daniel
authors: D
authors: Kolarich
authors: Mark S
authors: MS
authors: Baker
authors: William S
authors: WS
authors: Hancock
authors: Nicolle H
authors: NH
authors: Packer
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002846:Chromatography, Affinity / Q000379:methods; D045424:Complex Mixtures / Q000737:chemistry*; D003208:Concanavalin A / Q000378:metabolism; D054794:Glycomics; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D008099:Liver / Q000737:chemistry / Q000166:cytology; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D010936:Plant Extracts / Q000737:chemistry; D037121:Plant Lectins / Q000378:metabolism; D051381:Rats; D014909:Wheat Germ Agglutinins / Q000378:metabolism
chemical_list: D001798:Blood Proteins; D045424:Complex Mixtures; D006023:Glycoproteins; D037102:Lectins; D008565:Membrane Proteins; D010936:Plant Extracts; D037121:Plant Lectins; D014909:Wheat Germ Agglutinins; C043696:jacalin; D003208:Concanavalin A