Patent ID: 6440687
Filing Date: 2002-08-27
Classification: G01N

Abstract:
A method for determining the sequence of a test peptide or a test polypeptide comprising:(A) cleaving the amide backbone of the test peptide or the test polypeptide by treatment with Trypsin to form a sub-population of fragments having carboxy-terminal lysine or arginine residues; (B) ionizing said fragments to produce doubly charged gas phase ions; (C) further fragmenting the gas phase ions under conditions which produce a population of daughter ions of incremental molecular weight, which population of daughter ions results substantially from fragmentation of the amide backbone of said fragments; (D) determining the molecular weight of said gas phase ions and daughter ions by mass spectrometry; and (E) determining the sequence of at least a portion of the test peptide or the test polypeptide from the determined molecular weights.