Proteoglycans of bovine periodontal ligament and skin. Occurrence of different hybrid-sulphated galactosaminoglycans in distinct proteoglycans

Abstract

A proteoglycan purified from 4 M-guanidinium chloride extracts of bovine periodontal ligament closely resembled that of bovine skin, except for a rather lower protein content and a higher molecular weight (120 000 compared with about 90 000) by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The latter difference was explained by the molecular weights (29 000 and 16 000) of the respective dermatan sulphate components, each of which was rich in L-iduronate (about 75% of the total hexuronate). Significant amounts of other glycosaminoglycans did not occur in these proteoglycans, which were homogenous on gel chromatography and agarose/polyacrylamide-gel electrophoresis. Polydispersity was observed in sedimentation equilibrium experiments, but proteolysis or self-association of the proteodermatan sulphates may have affected these results. Ligament proteoglycans that were almost completely extracted with 0.1 M-NaCl contained less protein of a completely different amino acid composition than the proteodermatan sulphates. They were heterogeneous in size but generally smaller than cartilage proteoglycans and L-iduronate was a component, comprising about 7% of the total hexuronate of the sulphated galactosaminoglycan chains. The latter consisted of two fractions differing in molecular weight, but a dermatan sulphate with a high L-iduronate content was not present. These proteoglycans had some resemblance to D-glucuronate-rich proteoglycans of other non-cartilaginous tissues. Such compounds, however, are difficult to categorize at present.

A Biochemical and Immunohistochemical Study of the Proteoglycans of Alveolar Bone

“…The amino acid composition of alveolar bone proteoglycans appeared to differ from those derived from the soft tissues of the periodontium (gingiva and VO s 1t t_ Vt periodontal ligament). In these tissues the proteoglycans are V Lo at fl i v relatively poor in serene and glutamic acid residues (Pearson and Gibson, 1982;Bartold et al, 1983). Whether these represent significant differences between bone and soft-tissue proteoglycans remains to be established, because, although some immunological evidence suggests that the core proteins of the small proteoglycans of bone differ from their soft-tissue coun- terparts (Fisher et al, 1983), recent data indicate that the deduced protein sequences of bone and proteoglycans from other Fraction Number tissues show some degree of homology (Fisher et al, 1989).…”

“…§Values taken from results published by Bartold et al (1983). 'Values taken from results published by Pearson and Gibson (1982).…”

Characteristics of chondroitin sulfate proteoglycans of differentiating nonchondrogenic tissues

“…In several tissues of adult vertebrates such as ovarian fluid (35), ovarian granulosa (36), skin (37), periodontal ligament (26), cornea (38,39), aorta (40)(41)(42)(43)(44)(45), and cultured aortic endothelium (46), the proteoglycans contain glycosaminoglycan chains which are copolymers of chondroitin sulfate and dermatan sulfate. In addition, in bovine aorta a copolymer consisting of separate chains of derrnatan sulfate and chondroitin sulfate attached to the same core protein has been proposed (47).…”

“…Although many dermatan sulfates contain stretches of chondroitin sulfate (see Ref. 26 for review), such copolymers are not digested by chondroitinase AC of Arthrobacter aurescens, which is an exoenzyme (27), although presumably any chondroitin sulfate units at the free ends of such chains can be removed. Specific features which were studied in this manner were the relative sizes of the chondroitin sulfate chains released by papain and by p-elimination from the protein core and the susceptibility of the protein core to trypsin.…”

The periphery of the developing collagen fibril Quantitative relationships with dermatan sulphate and other surface-associated species

“…1 shows that the data for rat tail, bovine flexor and chick zone-2' tendons cluster closely to the best-fit line, implying that the relationship is indeed linear, Since the points from three differei cluster about the same line, it is implied is little species difference in the constant tionality, k', between dermatan sulpha glycan and collagen-fibril surface a suggests that this interaction will be fe evolutionarily highly conserved. This expected, if speculations on the effect fication and fibril cross-linking of the pla dermatan sulphate proteoglycan at the (Scott & Orford, 1981) Coster, 1979;Fuji & Nagai, 1981; onate with Pearson & Gibson, 1982), the number of dermatan t constant proteoglycan molecules associated with the surface th those of of a D unit of a collagen fibril of diameter 50nm is of the order of 10-20 (Scott et al, 1983 N-terminal extension propeptides are probably regularly present at the periphery of the collagen fibril, but the ratios are about 100-fold less than the calculated expected value, suggesting that conversion from procollagen is essentially complete, during the developmental period studied.…”