Type IX collagen from sternal cartilage of chicken embryo contains covalently bound glycosaminoglycans.

Publisher Website
Google Scholar
Abstract
Type IX collagen was isolated as a native protein from chicken embryo sternal cartilages and purified to homogeneity. Chondroitin and/or dermatan sulfate were bound covalently to 1 of the 3 polypeptide chains present in this protein containing collagenous and noncollagenous domains. Type IX collagen could be metabolically labeled with both radioactive sulfate and Gly. The protein containing either of these labels was sensitive to digestion by bacterial collagenase as well as chondroitinase ABC. Besides the glycosaminoglycans, type IX collagen contains As-linked carbohydrate chains because the protein could be labeled with radioactive mannose and no glycosaminoglycans other than those mentioned above were present. The melting curve indicated that, in contrast to interstitial collagens, this molecule contains at least 2 disulfide-bonded collagenous domains with distinct thermal stabilities.