title: 13C-NMR spectral study of reductively [13C]methylated glycophorin B.
abstract: Glycophorin BN was reductively [13C]methylated and the 13C chemical shift of the N-terminal [13C]dimethyl-leucine residue was monitored as a function of pH. These results were compared to the pH-dependent chemical shift studies of the N-terminal [13C]dimethylleucine residues of intact glycophorin AN and N-terminal glyco-octapeptide AN. The results indicate that the titration data for [13C]dimethylleucine of glycophorin BN more closely resembles the titration data observed for the [13C]dimethylleucine residue of the N-terminal glyco-octapeptide AN rather than for the [13C]dimethylleucine residue of intact glycophorin AN. Integration of the 13C resonances indicated that glycophorin BN contains 3-4 lysine residues.
mesh_terms: D006021:Glycophorins; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008951:MNSs Blood-Group System; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D010084:Oxidation-Reduction; D012795:Sialoglycoproteins
chemical_list: D006021:Glycophorins; D008951:MNSs Blood-Group System; D012795:Sialoglycoproteins