Amide Hydrogen/Deuterium Exchange by Top - Down El ectron Capture Dissociation - Fourier Transform Ion Cyclotron Mass Spectrometry

摘要

Although amide hydrogen/deuterium exchange (HDX) coupled with mass spectrometry (MS) is widely accepted for the study of protein dynamics, its utility to provide cleavage site information when coupled with Electron Capture Dissociation (ECD) in a Top-Down approach is a point of debate. In the present work, ECD FTICR MS was used to investigate amide hydrogen/ deuterium exchange on both Substance P and Ubiquitin in solution phase. HPLC separation eliminated the influence of deuterium exchange with amino acid side chain and the terminal protons in Substance P. Furthermore, the use of the separation and analysis of amide HDX of individual charge states in Ubiquitin to differentiate solution phase conformations was demonstrated.