Lectin‐based structural glycomics: A practical approach to complex glycans

Abstract

Glycans exist in nature in various forms of glycoconjugates, i.e., glycoproteins, glycolipids, and glycosaminoglycans, either in soluble or membrane-bound forms. One of their prominent properties distinguished from nucleic acids and proteins is "heterogeneity" largely attributed to their inherent features of biosynthesis. In general, various methods based on the physicochemical principles have been taken for their separation and structural determination although all of them require prior liberation of glycans and appropriate labeling. On the other hand, a series of carbohydrate-binding proteins, or "lectins," have extensively been used in a more direct manner for cell typing, histochemical staining, and glycoprotein fractionation. Although most procedures conventionally used are useful, unfortunately they lack "throughput" comparable to a performance required for current omics studies. Recently, a novel technique called lectin microarray has attracted increasing attention from not only glycoscientists but also researchers in other fields, because it is straightforward and also informative. The method is innovating in that it enables direct approach to glycoconjugates such as glycoproteins and even cells without liberation of glycans from the core substrate, and therefore can be effectively applied for the sake of differential profiling in various fields. Concept, strategy, and technical advancement of lectin microarray are described. Also, as an introduction to glycomics, the authors explain the motivation to challenge this theme.

A lectin-based approach to detecting carcinogenesis in breast tissue

“…A and sialyl Lewis X structures observed in breast cancer are considered to be involved in lymph node metastasis (22,25). Overexpression of sialyl Lewis A , sialyl Lewis X and TF antigen has also been reported in other types of cancer (26).…”

Conformational change of a unique sequence in a fungal galectin from Agrocybe cylindracea controls glycan ligand‐binding specificity

“…Recently, a lectin microarray has been developed to identify specific saccharides and for diagnostic applications [21][22][23]. The lectins used as the probes in the array are mostly from natural [26].…”

Crystallization and preliminary X-ray diffraction studies of frutalin, an α-D-galactose-specific lectin fromArtocarpus incisaseeds

“…Lectins have the unique ability to discriminate complex glycoconjugate structures without altering their molecular structure (Hirabayashi et al, 2011). Several lectins have been characterized in almost all groups of organisms, including viruses, but they are particularly prominent in plant seeds, particularly leguminous seeds.…”