Abstract
Sulfated galactosaminoglycans of mature bovine periodontal ligament were separated into four fractions by ethanol precipitation. Fractions I and II were dermatan sulfates with high contents of L-iduronate, but only small amounts of this hexuronic acid were present in fractions III and IV. Effects of digestion with testicular hyaluronidase or a periodate-alkali treatment showed that most if not all of the glycans in fractions I, II and III were hybrid chains containing both L-iduronate and D-glucuronate. The composition of fraction IV was less certain, but the chains strongly resembled fraction III hybrids in electrophoretic characteristics, not chondroitin sulfate. The total amount of the D-glucuronate-rich fractions III and IV in the ligament was similar to that of I plus II. In contrast, almost all of the sulfated galactosaminoglycans of mature skin were rich in L-iduronate. The more varied composition of the ligament glycosaminoglycans may be related to the mixed population of cells in this tissue.