Enhanced Characterization of Membrane Protein Complexes by Ultraviolet Photodissociation Mass Spectrometry

Anal Chem. 2020 Jan 7;92(1):899-907. doi: 10.1021/acs.analchem.9b03689. Epub 2019 Dec 10.

Abstract

Development of chemical chaperones to solubilize membrane protein complexes in aqueous solutions has allowed for gas-phase analysis of their native-like assemblies, including rapid evaluation of stability and interacting partners. Characterization of protein primary sequence, however, has thus far been limited. Ultraviolet photodissociation (UVPD) generates a multitude of sequence ions for the E. coli ammonia channel (AmtB), provides improved localization of a possible post-translational modification of aquaporin Z (AqpZ), and surpasses previous reports of sequence coverage for mechanosensitive channel of large conductance (MscL). Variations in UVPD sequence ion abundance have been shown to correspond to structural changes induced upon some perturbation. Preliminary results are reported here for elucidating increased rigidity or flexibility of MscL when bound to various phospholipids.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aquaporins / chemistry*
  • Cation Transport Proteins / chemistry*
  • Escherichia coli / chemistry*
  • Escherichia coli Proteins / chemistry*
  • Ion Channels / chemistry*
  • Mass Spectrometry / methods
  • Models, Molecular
  • Photolysis
  • Protein Processing, Post-Translational
  • Ultraviolet Rays

Substances

  • AmtB protein, E coli
  • Aquaporins
  • Cation Transport Proteins
  • Escherichia coli Proteins
  • Ion Channels
  • MscL protein, E coli
  • aqpZ protein, E coli