The nature of collagen-chondroitin sulphate linkages in tendon

Abstract

In previous communications it has been suggested that chondroitin sulphate plays an important part in stabilizing the structure of tendon What little evidence is available suggests that the mucopolysaccharide is firmly linked to the collagen of tendon Einbinder & Schubert (1951) found that the uptake of chondroitin sulphate by purified tendon collagen was maximal at pH 3 and minimal in the physiological pH range, and on this evidence they suggested that the linkage is not salt-like. Morner (1889) held that chondroitin sulphate occurred in cartilage as an alkali-metal salt, while Meyer, Partridge (1948) favours an explana- tion half-way between these two extremes, and considers that the strongly acidic sulphate groups are held in combination with some of the basic protein residues, the net charge of the complex being adjusted mainly by competition between alkali- metal ions and hydrogen ions for carboxylic acid residues in both protein and polysaccharide. Woodin (1952) considers that in cornea the collagen-