Structures of Glycoproteins

In order to investigate, and deduce, the complex carbohydrate structures of glycoproteins, it must be possible to release, and isolate, the oligosaccharide chain(s) from the glycoprotein. Following this, the structure is usually deduced by a combination of enzymic, chemical, and instrumental methods.34-36... 

Multiple-ion monitoring is, however, of considerable value in structural studies, but only if model compounds of known structure are available for comparison. Such an approach has been used in the study of the carbohydrate structures of glycoproteins from different tissues.50 Separation of glycopeptides obtained from various tissues was performed on columns of concanavalin A-Sepharose. Structural analysis by multiple-ion monitoring of partially methylated, alditol acetates derived from the various fractions indicated that the glycopeptides were separated according to the linkage pattern of mannose (see Fig. 1). 

In connection with the structure of glycoproteins, Lloyd and Kabat studied the separation of six alditol acetates,452 and Kim and coworkers57 examined the separation of L-fucitol, D-glucitol, D-manni-tol, and galactitol. Alditol acetates have been used in studies on... 

Fig. 18. Structure and blood clearance of synthetic HPMA copolymers mimicking the structure of glycoproteins and asialoglycoproteins. Based on data from [261]...

Differences in the structure of glycoproteins can manifest themselves in a number of ways. Perhaps the first point to be emphasized is that the nature of the polypeptide chain to which oligosaccharide moieties become attached is not always the same. This is a situation that we have already discussed in connection with certain of the glycosaminoglycans (see p. 440). 

J. Montreuil, Primary structure of glycoproteins glycans Bases for the molecular biology ol glycoproteins, Adv. Carbohydr. Chem. Biochem. 37 153 (1980). 

PRIMARY STRUCTURE OF GLYCOPROTEIN GLYCANS BASIS FOR THE MOLECULAR BIOLOGY OF GLYCOPROTEINS... 

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