Characterization of a non-reducing terminal fragment from bovine articular cartilage keratan sulphates containing alpha(2-3)-linked sialic acid and alpha(1-3)-linked fucose

Alkaline-borohydride-reduced keratan sulphate chains were isolated from bovine articular cartilage (6-8-year-old animals) and digested with keratanase II, an endo-beta-N-acetylglucosaminidase. The resulting oligosaccharides were borohydride-reduced and fractionated on a strong anion-exchange column. H-1-NMR spectroscopic analysis of the products revealed one containing both alpha(2-3)-linked sialic acid and alpha(1-3)-linked fucose which was shown to have the structure (I) shown. This structure is a sulphated variant of the VIM-2 epitope (CD65), a putative ligand of E-selectin. No oligosaccharide containing the sialyl-Le(x) structure [NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-] was identified in this study.