sepharose and acetic-anhydride

The effect of a "bisecting" 2-acetamido-2-deoxy-beta-D-glucopyranosyl group, linked (1----4) to the beta-D-mannopyranosyl group of asparagine-linked complex and hybrid oligosaccharides, on the binding of [14C]acetylated glycopeptides to columns of immobilized concanavalin A (Con A), Phaseolus vulgaris erythroagglutinin (E-PHA), and Ricinus communis agglutinin-120 (RCA-120) was investigated. The presence of this "bisecting" GlcNAc group caused significant inhibition of the binding to ConA-agarose of biantennary complex glycopeptides in which the two branches are terminated at their nonreducing ends by two GlcNAc groups, or by a Gal and a GlcNAc group, or by two Gal groups, or by a Man and a GlcNAc group. Binding of biantennary, complex glycopeptides to E-PHA-agarose required a "bisecting" GlcNAc group, a Gal group at the nonreducing terminus of the alpha-D-Man-p-(1----6) branch, and a terminal or internal GlcNAc residue linked beta-(1----2) to the alpha-D-Manp-(1----3) branch. Binding to RCA-120-agarose occurred only when at least one nonreducing terminal Gal group was present, and increased as the proportion of terminal Gal groups increased; the presence of a "bisecting" GlcNAc group caused either enhancement or inhibition of these binding patterns. It is concluded that a "bisecting" GlcNAc group affects the binding of glycopeptides to all three lectin columns.

Topics: Acetic Anhydrides; Acetylation; Acetylglucosamine; Carbohydrate Conformation; Carbohydrate Sequence; Carbon Radioisotopes; Concanavalin A; Glucosamine; Glycopeptides; Lectins; Oligosaccharides; Phytohemagglutinins; Plant Lectins; Plants, Toxic; Ricin; Ricinus communis; Sepharose