Structure of the N‐Linked Oligosaccharides from Tridacnin, a Lectin Found in the Haemolymph of the Giant Clam Hippopus Hippopus

Abstract

Tridacnin, a glycoprotein lectin, was isolated from the symbiotic marine clam Hippopus hippopus and the structure of its major N‐glycan chains determined. Tridacnin contains only N‐linked glycans which were quantitatively cleaved by peptide‐N4‐(N‐acetyl‐β‐glucosaminyl)asparagine amidase F. Following purification by anion‐exchange HPLC, the structures of the oligosaccharides were established using a combination of electrospray ionisation mass spectrometry, 1H‐NMR spectroscopy and linkage analysis. The N‐glycans are primarily of the oligomannose type but, in addition, some contain a novel 6‐O‐Me group on the terminal mannose residue of the chain. The N‐glycan chains had the following structures. (Formula Presented.) Copyright © 1995, Wiley Blackwell. All rights reserved