Structures of novel sialylated O-linked oligosaccharides isolated from human erythrocyte glycophorins.

The O-linked oligosaccharides attached to human erythrocyte glycophorins were extensively characterized. In addition to the previously described disialylated tetrasaccharide, NeuNAc alpha 2—3Gal beta 1—3 (Neu-NAc alpha 2—6)GalNAcOH and monosialylated trisaccharide, NeuNAc alpha 2—3Gal beta 1—3GalNAcOH, novel trisialylated oligosaccharides were isolated. Methylation analysis, fast atom bombardment-mass spectrometry, and enzymatic degradation were used to elucidate the following novel structures: formula; see text: These results suggest that O-linked oligosaccharides with a disialosyl group, NeuNAc alpha 2—8NeuNAc alpha 2—, may be present in various tissues.