N-acetyllactosaminooligosaccharides that contain the beta-D-GlcpNAc-(1----6)-D-Gal or beta-D-GlcpNAc-(1----6)-D-GalNAc sequences reveal reduction-sensitive affinities for wheat germ agglutinin.
Affinity chromatography of unreduced oligosaccharides on a small column of immobilized wheat germ agglutinin (WGA) revealed high-binding affinities for several radiolabeled molecules containing at the reducing end either beta-D-GlcpNAc-(1----6)-D-Gal, beta-D-GlcpNAc-(1----6)-beta- D-Galp-(1----4)-D-GlcNAc, beta-D-GlcpNAc-(1----6)-beta-D-Galp-(1----4)DGlc, D-GlcpNAc-(1----3)-[beta-D-GlcpNAc-(1----6)]-D-Gal, beta-D-GlcpNAc-(1----6)- D-GalNAc, or beta-D-Galp-(1----3)-[beta-D-GlcpNAc-(1----6)]-D-GalNAc sequences. Reduction changed the binding affinities remarkably: The sequences carrying a D-galactose or 2-acetamido-2-deoxy-D-galactose residue at the reducing end lost most of their affinities, but the sequences containing a D-glucose or 2-acetamido-2-deoxy-D-glucose residue at the reducing end gained additional affinity upon reduction. These findings emphasize the role of the unreduced, 6-o-substituted D-galactose and 2-acetamido-2-deoxy-D-galactose residues for the binding of saccharides to WGA, which has been recognized previously as a lectin specific for oligosaccharides containing a 2-acetamido-2-deoxy-D-glucose or sialic acid unit. The results suggested also that WGA-agarose chromatography of alditols may become a valuable method for the fractionation of oligo-N-acetyllactosaminoglycans and related saccharides.
Institute of Biotechnology, University of Helsinki, Finland.
O
O
Renkonen
L
L
Penttilä
R
R
Niemelä
A
A
Vainio
A
A
Leppänen
J
J
Helin
A
A
Seppo
A
A
Makkonen
H
H
Maaheimo
D000606:Amino Sugars / Q000737:chemistry / Q000378:metabolism; D002240:Carbohydrate Sequence; D002846:Chromatography, Affinity; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D014909:Wheat Germ Agglutinins / Q000378:metabolism*
D000606:Amino Sugars; D009844:Oligosaccharides; D014909:Wheat Germ Agglutinins; C000458:N-acetyllactosamine