Structures of sugar chains of the third component of human complement.
Human C3, the third component of human complement, contained mannose and N-acetylglucosamine as sugar components. The sugar chains were liberated from the polypeptide chains by hydrazinolysis, and the free amino groups were N-acetylated. The reducing end residues of the sugar chains thus obtained were tagged with 2-aminopyridine, and the pyridylamino (PA-) derivatives of sugar chains were separated by high-performance liquid chromatography. The structures of purified PA-sugar chains were analyzed by a combination of stepwise exoglycosidase digestions, size determination by paper electrophoresis, methylation analysis, Smith degradation, and partial acetolysis. These results showed that C3 contained two high-mannose type sugar chains ranging from Man5GlcNAc2 to Man9GlcNAc2. Analyses of the sugar chains of alpha- and beta-chains of C3 indicated that the alpha-chain contained mainly Man8GlcNAc2 and Man9GlcNAc2, while the beta-chain contained mainly Man5GlcNAc2 and Man6GlcNAc2.
D000085:Acetates; D019342:Acetic Acid; D000596:Amino Acids / Q000032:analysis; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D003176:Complement C3; D006801:Humans
D000085:Acetates; D000596:Amino Acids; D002241:Carbohydrates; D003176:Complement C3; D019342:Acetic Acid