The Linkage Region

Fig. 5. —Tentative Model for a Heparin Chain Containing the Linkage Region. [1 and 2 are sites of cleavage with 2-pyridone, affording fragments A and B A may be further cleaved by a more drastic treatment. The active site for antithrombin is proposed - 8 to be within fragment A. ...

Synthesis of an O-Linked Glycopeptidomimetic (Glycopeptoid) Corresponding to the Linkage Region of Proteoglycans... 

Evidence for the structure of the main repeating-chain of chondroitin sulfate, as well as the sequence at the linkage region to protein, has come... 

Two types of keratan sulfate, corneal and skeletal, have been differentiated by the hydrolytic behavior of the linkage region. The former has an N-... 

In the polymers of groups (1) and (2), polysaccharide chains composed of oligosaccharide repeating-units (sometimes, partially modified) are usually linked to a unique oligosaccharide unit present near the point of attachment of the chain to another polymeric chain, or to a lipid anchor. This unit is called the linkage region in the polymers of bacterial cell-wall, and the core region in lipopolysaccharides. 

With respect to polysaccharides, N-acetylneuraminic acid and KDO are unusual components. Rather, N-acetylneuraminic acid is a constituent of glycoproteins and certain glycolipids - and KDO is characteristically found in enterobacterial lipopolysaccharides, where it forms the linkage region between the lipid and carbohydrate moieties. 

Kunz, H., Waldman, H., and Marz, J. (1989) Synthesis of partial structures of A-glycopeptides representing the linkage regions of the transmembrane neuraminidase of an influenza virus and of factor B of the human complement system. Liebigs Ann. Chem. (1), 45 19. 

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