Open AccessDetergent-free Lipodisq Nanoparticles Facilitate High-Resolution Mass Spectrometry of Folded Integral Membrane Proteins
Author(s) -
Kin Kuan Hoi,
Juan F. Bada Juarez,
Peter J. Judge,
HsinYung Yen,
Di Wu,
Javier Viñals,
Garrick F. Taylor,
Anthony Watts,
Carol V. Robinson
Publication year - 2021
Publication title -
nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.853
H-Index - 488
eISSN - 1530-6992
pISSN - 1530-6984
DOI - 10.1021/acs.nanolett.0c04911
Subject(s) - bacteriorhodopsin , integral membrane protein , chemistry , membrane protein , mass spectrometry , membrane , nanodisc , biophysics , micelle , biochemistry , chromatography , organic chemistry , biology , aqueous solution
Integral membrane proteins pose considerable challenges to mass spectrometry (MS) owing to the complexity and diversity of the components in their native environment. Here, we use native MS to study the post-translational maturation of bacteriorhodopsin (bR) and archaerhodopsin-3 (AR3), using both octyl-glucoside detergent micelles and lipid-based nanoparticles. A lower collision energy was required to obtain well-resolved spectra for proteins in styrene-maleic acid copolymer (SMA) Lipodisqs than in membrane scaffold protein (MSP) Nanodiscs. By comparing spectra of membrane proteins prepared using the different membrane mimetics, we found that SMA may favor selective solubilization of correctly folded proteins and better preserve native lipid interactions than other membrane mimetics. Our spectra reveal the correlation between the post-translation modifications (PTMs), lipid-interactions, and protein-folding states of bR, providing insights into the process of maturation of the photoreceptor proteins.