A novel type of carbohydrate structure present in hen ovomucoid

Hen ovomucoid is characterized by a high degree of microheterogeneity of its carbohydrate moieties, as was recently demonstrated by hydrazinolysis in combination with high performance liquid chromatography (Paz Parente, J., Strecker, G., Leroy, Y., Montreuil, J., and Fournet, B. (1982) J. Chromatogr., in press). This approach resulted in 17 oligosaccharide-alditol fractions; the major one could be purified to homogeneity. Primary structural analysis of this fraction was carried out by methylation analysis, partial acid hydrolysis, and 500-MHz 1H NMR spectroscopy. Combination of these techniques enabled the unambiguous determination of a novel type of asparagine-bound carbohydrate chain: (formula, see text).