Patent ID: 7729868

Claim:
A method for analyzing a structure of glycoprotein or glycopeptide comprising the steps of: (A) conducting an MS analysis of a single sample of a glycoprotein or a glycopeptide using a mass spectrometer capable of conducting a second or higher order MS analysis to obtain (i) an A-adducted molecule represented by [M+A] + in which a positively charged ion A + that is likely to add to a protein or a peptide adds to a specific glycoprotein molecule or a specific glycopeptide molecule M and (ii) a B-adducted molecule represented by [M+B] + in which a positively charged ion B + that is likely to add to a sugar chain adds to the specific glycoprotein molecule or the specific glycopeptide molecule M; (B) conducting a second or higher order MS n analysis by selecting said A-adducted molecule represented by [M+A] + measured in said MS analysis as a precursor ion to obtain an A-adducted glycoprotein or glycopeptide and by selecting said B-adducted molecule represented by [M+B] + measured in said MS analysis as a precursor ion to obtain a B-adducted sugar chain; (C) identifying a primary structure of a protein or a peptide and a sugar chain binding site using said A-adducted glycoprotein or glycopeptide; and (D) identifying a primary structure of a sugar chain using said B-adducted sugar chain.