Title : Structures of
sugar chains of the third component of human complement
Abstract :
- 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.