Combined Chemical Modification and Collision Induced Unfolding Using Native Ion Mobility‐Mass Spectrometry Provides Insights into Protein Gas‐Phase Structure

Native mass spectrometry is now an important tool in structural biology. Thus, the nature of higher protein structure vacuum spectrometer area significant interest. One major goals study gas-phase to elucidate stabilising role interactions at level individual amino acid residues. A strategy combining chemical modification together with collision induced unfolding (CIU) was developed and employed probe compact ions produced by native electrospray ionisation. Tractable used alter properties residues, ion mobility-mass (IM-MS) utilised monitor extent as a function modification. From these data importance specific intramolecular for stability can be inferred. Using this approach, aided molecular dynamics simulations, interaction between K6 H68 ubiquitin identified, contact N-terminus E22 binding UBA2.