Purification and structural characterization of a cartilage matrix protein.
The cartilage matrix protein is a major non-collagenous protein in bovine cartilage. It was purified from a 5 M-guanidinium chloride extract of bovine tracheal cartilage by sequential CsCl-density-gradient centrifugation, gel chromatography in guanidinium chloride and differential precipitation. The molecular weight of the intact protein is 148 000, determined by sedimentation-equilibrium centrifugation. It was dissociated to three subunits of molecular weight 52 000 by reduction of disulphide bonds. The cartilage matrix protein was insoluble in low-salt solutions and behaved abnormally on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The content of cysteine was high, whereas the contents of aromatic amino acids were low. The carbohydrate content was 3.9% (w/w). Glycopeptides obtained after papain digestion were heterogenous on gel chromatography. Asparagine/aspartic acid was enriched in the purified glycopeptides, indicating the presence of N-glycosidic linkages to protein.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D002356:Cartilage / Q000032:analysis*; D002417:Cattle; D002499:Centrifugation, Density Gradient; D055598:Chemical Phenomena; D002621:Chemistry; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins / Q000302:isolation & purification; D064235:Matrilin Proteins; D008970:Molecular Weight
D000596:Amino Acids; D002241:Carbohydrates; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins