Proteo glycans of bovine periodontal ligament and skin occurrence of different hybrid sulfated galactosamino glycans and in distinct proteo glycans
Pearson, C.H.; Gibson, G.J.
Biochemical Journal 201(1): 27-38
ISSN/ISBN: 0264-6021 Accession: 006214374
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 MW (120,000 compared with .apprx. 90,000) by sodium dodecyl sulfate/polyacrylamide electrophoresis. The latter difference was explained by the MW (29,000 and 16,000) of the respective dermatan sulfate components, each of which was rich in L-iduronate (.apprx. 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 sulfates 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 sulfates. They were heterogeneous in size but generally smaller than cartilage proteoglycans, and L-iduronate was a component, comprising .apprx. 7% of the total hexuronate of the sulfated galactosaminoglycan chains. The latter consisted of 2 fractions differing in MW, but a dermatan sulfate with a high L-iduronate content was not present. These proteoglycans had some resemblance to D-glucuronate-rich proteoglycans of other noncartilaginous tissues. Such compounds are difficult to categorize at present.