Carbon-13 nuclear magnetic resonance study of chondroitin 4-sulfate in the proteoglycan of bovine nasal cartilage.

The Fourier transform 13C nuclear magnetic resonance spectra of bovine nasal cartilage proteoglycan subunit and complex and whole bovine nasal cartilage were obtained and compared with that of chondroitin 4-sulfate. The spectrum of chondroitin 4-sulfate in solution revealed multiple resolvable resonances with linewidths that are consistent with considerable segmental motion in the polysaccharide chain. The spectra of proteoglycan subunit and complex in solution and that of whole cartilage were very similar to that of free chondroitin 4-sulfate chains. This indicates that the linkage of multiple chondroitin sulfate chains to proteoglycan core protein and the association of proteoglycan with collagen and other constituents of cartilage matrix does not significantly alter the structure and motions of these chains.