Proteoglycans and Glycoproteins

Lennarz, W. J., 1980. The Biochemistry of Glycoproteins and Proteoglycans. New York Plenum Press. 

Figure 47-2. Structures of two 0-linked oligosaccharides found in (A) submaxillary mucins and (B) fe-tuin and in the sialoglycoprotein of the membrane of human red blood cells. (Modified and reproduced, with permission, from LennarzWJ The Biochemistry of Glycoproteins and Proteoglycans. Plenum Press, 1980.)...

An attempt to use the infrared spectrum of materials collected at the sea surface for a quantitative measure of composition has been made by Baier et al. [285]. They dipped a germanium crystal through the surface film, then ran an internal reflectance spectrum on the material clinging to the crystal. From the spectrum, they concluded that the bulk of the material present in the surface film was there as glycoproteins and proteoglycans. 

Dietary sugars are also modified for synthesis of glycoproteins and proteoglycans, especially for serum proteins and extracellular matrix structural proteins. 

Herring, G. M., Ashton, B. A., Chipperfield, A. R. The isolation of soluble proteins, glycoproteins, and proteoglycans from bone. Prep. Biochem. 4, 179 (1974)... 

Herring, G. M. Methods for the study of the glycoproteins and proteoglycans of bone using bacterial collagenase. Determination of bone sialoprotein and chondroitin sulphate. Calc. Tiss. Res. 24, 29 (1977)... 

Other phosphoproteins, glycoproteins, and proteoglycans may also be required for mineralization. For example, the 286-residue glycoprotein osteonectin323 700 701 accounts for 3% of total bone protein. It contains two Ca2+-binding motifs and inhibits growth of hydroxylapatite crystals, but its role in bone development is not clear. One of the phosphoproteins of developing bone has been identified as... 

This concept, known as273"275 the one enzyme-one linkage concept, has been widely used in discussions of the biosynthesis of carbohydrate chains in animal glycoproteins and proteoglycans. It implies that the structure of a carbohydrate chain is dictated by the specificity of the enzymes that participate in glycosidic-bond formation. Application of the same concept for discussion of the biosynthesis of bacterial polysaccharides seems worth while. 

In the elucidation of the structures of the glycoproteins and proteoglycans, their behavior with respect to alkalies has played an important part. Although misinterpretations were made, the proper use of alkalies has given important information. The purpose of this paper is to show these applications and the problems involved. 

J.G. Beeley, Glycoprotein and Proteoglycan Techniques, Elsevier, New York, (1985). 

Recent studies have shown that all basement membranes contain a unique collagen arranged in an unusual network structure as well as certain glycoproteins and proteoglycans that occur only in basement membranes (Laurie et al., 1983). The cooccurrence of these proteins in basement membranes is due both to their synthesis by the cells that lie along the basement membrane and to strong and specific interactions that maintain the components together in situ. Also, the cells on basement membranes have specific receptors for these components (Yamada, 1983 von der Mark and Kiihl, 1985 Kleinman et al., 1985 Martin and Timpl, 1987). 

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