Abstract
The past half a century has witnessed a tremendous progress in structural determination of glycans in glycoconjugates. From the establishment of GlcNAc-Asn linkage in glycoproteins, a common core structure in N-glycans was soon elucidated. Subsequent meticulous structural studies utilizing chromatographic separation of labeled oligosaccharides accompanied by various chemical and enzymatic methods led to hundreds of established structures. Advancement in instrumentation (e.g., high performance liquid chromatography and nuclear magnetic resonance) was indispensable in the process, and now mass spectrometry of different modes has become essential, especially for high-throughput elucidation of structures. As more and more structures become known, the importance of database also has increased. All these progress contribute to expanded realm of glycomics and proteoglycomics.