Extending native mass spectrometry approaches to integral membrane proteins

Area of Science:

• Biochemistry and Biophysics
• Structural Biology
• Analytical Chemistry

Background:

• Membrane protein complexes are vital drug targets.
• Analyzing their dynamic structures is challenging.
• Native mass spectrometry (MS) and ion mobility (IM) offer new analytical capabilities.

Purpose of the Study:

• To review experimental strategies for analyzing membrane protein complexes using native MS and IM.
• To discuss methods for elucidating dynamic structures, lipid interactions, and conformational states.
• To evaluate reconstitution systems for compatibility with native MS.

Main Methods:

• Native mass spectrometry coupled with ion mobility.
• Nano-electrospray ionization of natively reconstituted proteins.
• Evaluation of lipid- and detergent-based reconstitution systems.
• Gas-phase analysis of intact, folded membrane proteins.

Main Results:

• Native MS and IM enable gas-phase analysis of membrane protein complexes.
• Strategies allow elucidation of dynamic structures, including lipid binding effects.
• Detection of co-populated conformational and assembly states is possible.
• Compatibility of reconstitution systems with native MS has been assessed.

Conclusions:

• Native MS and IM provide powerful tools for investigating membrane protein complexes.
• The discussed strategies facilitate studies on subunit composition, stoichiometry, and oligomeric state.
• Conformational changes, lipid binding, and drug interactions can be effectively studied.
• This approach is valuable for understanding integral membrane proteins as drug targets.