Chondroitin sulfate types

As shown in Figure 48-8, the keratan sulfates consist of repeating Gal-GlcNAc disaccharide units containing sulfate attached to the 6 position of GlcNAc or occasionally of Gal. Type 1 is abundant in cornea, and type II is found along with chondroitin sulfate attached to hyaluronic acid in loose connective tissue. Types I and II have different attachments to protein (Figure 48—8). 

In various types of arthritis, proteoglycans may act as autoantigens, thus contributing to the pathologic feamres of these conditions. The amount of chondroitin sulfate in cartilage diminishes with age, whereas the amounts of keratan sulfate and hyaluronic acid increase. These changes may contribute to the development of osteoarthritis. Changes in the amounts of cer-... 

The dermis contains several types of cells, including fibroblasts, fat cells, macrophages, histiocytes, mast cells, and cells associated with the blood vessels and nerves of the skin. The predominant cell is the fibroblast, which is associated with biosynthesis of the fibrous proteins and ground substances such as hyaluronic acid, chondroitin sulfates, and mucopolysaccharides. 

Enzymic transfer of D-xylose from uridine 5 -(D-xylopyranosyI-HC pyrophosphate) to L-serine residues of endogenous protein acceptors from (a) a cell tumor of the mouse188 and (b) chick-embryo cartilage189 occurs in cell-free extracts of both of these tissues, in the absence of biosynthesis of protein. The enzyme preparations employed were from the supernatant liquor, although activity was also present in the insoluble fractions. In these two types of tissue, the acceptors are heparin and chondroitin sulfate, respectively, but the presence of other D-xylose-containing glycoproteins in ascites fluid from... 

Fig. 4.1.8 Thin-layer chromatography of patient urines and a normal control. The MPS types are indicated beneath each band. The positions of dermatan sulfate (DS), heparan sulfate (HS), chondroitin sulfate (CS), and keratan sulfate (KS) are given on the right. The chromatogram was kindly provided by Professor E. Paschke, Laboratory of Metabolic Disease, Department of Pediatrics, University of Graz, Austria...

Figure 9.13 Structures of repeating units of glycosaminoglycans (A) hyaluronic acid (B) chondroitin sulfate (C) dermatan sulfate (D) two types of keratan sulfate type I is N linked and type II is O linked (E) heparan sulfate. Sulfate residues have been omitted in all cases.

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