Structural analysis of the oligosaccharide alditols released from the jelly coat of Rana dalmatina eggs by reductive β-elimination

A combination of ion-exchange chromatography and high performance liquid chromatography (HPLC) has been used to separate the reduced oligosaccharides produced by alkaline borohydride degradation of oviducal mucins obtained from the jelly coat of Rana dalmatina. The primary structures of 26 O-glycans were determined by one-dimensional and two-dimensional H-1 and (HC)-H-1-C-13 NMR spectroscopy. As observed for 20 other amphibian species, these carbohydrate chains are highly species-specific. The main typical feature of the species R. dalmatina consists in the presence of the backbone Gal(beta1-3)[Gal(beta1-4)]Gal(beta1-3)GalNAc-ol, previously observed among Ranidae, such as R. temporaria and R. ridibunda. Nevertheless, the nature of carbohydrates present at the periphery of the glycans perfectly differentiates the three species. (C) 2002 Societe francaise de biochimie et biologie moleculaire/Editions scientifiques et medicales Elsevier SAS. All rights reserved.