Generation of Charge-Reduced Ions of Membrane Protein Complexes for Native Ion Mobility Mass Spectrometry Studies

  • John W. Patrick
  • Arthur LaganowskyEmail author
Research Article


Recent advances in native mass spectrometry (MS) have enabled the elucidation of how small molecule binding to membrane proteins modulates their structure and function. The protein-stabilizing osmolyte, trimethylamine oxide (TMAO), exhibits attractive properties for native MS studies. Here, we report significant charge reduction, nearly threefold, for three membrane protein complexes in the presence of this osmolyte without compromising mass spectral resolution. TMAO improves the ability to resolve individual lipid-binding events to the ammonia channel (AmtB) by over 200% compared to typical native conditions. The generation of ions with compact structure and access to a larger number of lipid-binding events through the incorporation of TMAO increases the utility of IM-MS for structural biology studies.

Graphical Abstract


Native mass spectrometry Membrane protein Lipid Ion mobility 

Supplementary material

13361_2019_2187_MOESM1_ESM.docx (852 kb)
ESM 1 (DOCX 851 kb)


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Copyright information

© American Society for Mass Spectrometry 2019

Authors and Affiliations

  1. 1.Department of ChemistryTexas A&M UniversityCollege StationUSA
  2. 2.Janssen Research & DevelopmentSpring HouseUSA

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