'MALDI-MS~(3)' Analysis of peptides crosslinked by TEABS, an MS-cleavable isotopicallycoded crosslinker

摘要

Here we described "MALDI-MS~(3)" as a hypothesis driven MS~(2) analysis approach in which MS~(2) analysis of inter-peptide crosslinkswas used to identify fragment ions corresponding to the mass of individual peptides constituting the inter-peptide crosslinks. The fragment ions, cleaved in source during the initialMS~(2), were not detectable in the MS spectrum of the crosslinks. These fragments were selected for subsequent MS~(2). Thus,"MALDI-MS~(3)" analysis of DETA8.05 Da doublet fragments was able to provide sequence information for the individual peptide components of the crosslinks.