Gas-Phase Protein Salt Bridge Stabilities from Collisional Activation and Electron Transfer Dissociation.

ABSTRACT: The gas phase structures of several proteins have been studied by electron transfer dissociation (ETD) with and without prior collisional heating after electrospraying these proteins from native-like solutions into a quadrupole ion trap mass spectrometer. Without prior collisional heating, we find that ETD fragmentation is mostly limited to regions of the protein that are not spanned by the salt bridges known to form in solution. When protein ions are collisionally heated before ETD, new product ions are observed, and in almost all cases, these new ions arise from protein regions that are spanned by the salt bridges. Together these results confirm the existence of salt bridges in protein ions and demonstrate that a sufficient amount energy is required to disrupt these salt bridges in the g

SUBMITTER: Zhang Z 

PROVIDER: S-EPMC5646825 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature