Quaternary Diamines as Mass Spectrometry Cleavable Crosslinkers for Protein Interactions

摘要: Mapping protein interactions and their dynamics is crucial to defining physiologic states, building effective models for understanding cell function, allow more targeting of new drugs. Crosslinking studies can estimate the proximity proteins, determine sites protein–protein interactions, have potential provide a snapshot dynamic by covalently locking them in place analysis. Several major challenges are associated with use crosslinkers mass spectrometry, particularly complex mixtures. We describe synthesis characterization MS-cleavable crosslinker containing cyclic amines, which address some these challenges. The DC4 contains two intrinsic positive charges, crosslinked peptides fragment into component collision-induced dissociation (CID) or in-source decay. Initial fragmentation events result cleavage on either side charges so identified as pairs ions separated defined masses. structures then be robustly determined MS3 because products rearrange generate mobile proton. crosslinking reagent stable storage, highly reactive, soluble (1 M solutions), quite labile CID, results productive backbone fragmentation.