METHOD OF ANALYZING C-TERMINAL AMINO ACID SEQUENCE OF PEPTIDE USING MASS SPECTROMETRY

摘要

It is intended to provide a method of analyzing the C-terminal amino acid sequence of a peptide using a means of successively degrading the C-terminal amino acids, whereby the C-terminal amino acids of a peptide having a long amino acid sequence can be successively degraded while preventing undesirable side reactions (for example, cleavage of a peptide bond in the middle of the peptide) and the treatment can be performed under widely applicable conditions. The above method comprises preliminarily N-acylating a dry sample of a peptide having a long amino acid sequence, degrading the C-terminal amino acids under mild conditions with the use of a reagent comprising a combination of an alkanoic acid anhydride with a small amount of a perfluoroalkanoic acid, adding water, then digesting with trypsin to selectively fragment at an arginine residue site, and measuring a loss in the molecular weight in the C-terminal fragment caused by a series of reaction products with a MALDI-TOF-MS device to thereby specify the C-terminal amino acid sequence.