Proteinpolysaccharide of Bovine Cartilage

Evidence is presented which establishes that chondroitin sulfate and keratan sulfate are part of the same macromolecular proteinpolysaccharide in bovine nasal septum. Degradation of the proteinpolysaccharide with papain releases single chains of chondroitin sulfate with a characteristic residual peptide still attached. A larger molecular weight fragment contains the keratan sulfate which retains a different distribution of amino acids and some chondroitin sulfate chains which can be separated by treatment with alkali with the loss of serine and threonine residues. While the ratio of protein to chondroitin sulfate varies widely in proteinpolysaccharide, the ratio of protein to keratan sulfate remains remarkably constant and different methods of degradation which release single chains of chondroitin sulfate from the macromolecule normally retain the keratan sulfate in the high molecular weight residue.