STRUCTURE OF THE MAJOR NEUTRAL OLIGOSACCHARIDE-ALDITOLS RELEASED FROM THE EGG JELLY COATS OF AXOLOTL MACULATUM - CHARACTERIZATION OF THE CARBOHYDRATE SEQUENCE GALNAC(BETA-1-4)[FUC(ALPHA-1-3)] GLCNAC(BETA-1-3/6)

Several O-linked oligosaccharides of the jelly coat surrounding the eggs of Axolotl maculatum were analysed by IH-NMR spectroscopy. The four major oligosaccharide-alditols released by reductive beta-elimination display either the Lewis(x) (Le(x)) determinant or the sequence GalNAc(beta 1-4)[Fuc(alpha 1-3)]GlcNAc. This last structure has previously been characterized in allergenically active oligosaccharides isolated from the sea squirt H-antigen, and in the N-linked glycans of Schistosoma mansoni and human urokinase. It represents the major carbohydrate chain found in A.maculatum, the oviduct of which constitutes an excellent source of beta 1-4-acetylgalactosaminyl transferase activity. Moreover, the carbohydrate chains isolated from A.maculatum are quite different from those found in seven other amphibian species, in which the presence of species-specific material has been characterized. The role of carbohydrates appears more and more apparent during the fertilization process, and the diversity of the O-linked oligosaccharides supports such a biological role.