Selective spin labeling of terminal galactose and N-acetylgalactosamine residues on the membrane surface of erythrocytes.
A method to selectively spin label galactose and N-acetylgalactosamine residues of erythrocyte membrane glycoconjugates is described. The method is based on the activation of the C-6 CH2OH group of these two sugars by galactose oxidase followed by reductive amination with 2,2,6,6-tetramethyl-4-aminopiperidine-1-oxyl in the presence of a mild reducing agent, NaBH3CN. The extent and distribution of the spin labeling suggest that the major sialoglycoprotein, PAS-1, incorporates the greatest amount of spin label while the glycolipids incorporate less than 10% of the spin label.
D000116:Acetylgalactosamine / Q000032:analysis*; D003497:Cyclic N-Oxides; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000032:analysis*; D005688:Galactosamine / Q000031:analogs & derivatives*; D005690:Galactose / Q000032:analysis*; D006801:Humans; D008722:Methods; D013113:Spin Labels
D003497:Cyclic N-Oxides; D013113:Spin Labels; C015527:4-amino-TEMPO; D005688:Galactosamine; D000116:Acetylgalactosamine; D005690:Galactose