Modular detergents tailor the purification and structural analysis of membrane proteins including G-protein coupled receptors

Detergents enable the purification of membrane proteins and are indispensable reagents in structural biology. Even though a large variety of detergents have been developed in the last century, the challenge remains to identify guidelines that allow fine-tuning of detergents for individual applications in membrane protein research. Addressing this challenge, here we introduce the family of oligoglycerol detergents (OGDs). Native mass spectrometry (MS) reveals that the modular OGD architecture offers the ability to control protein purification and to preserve interactions with native membrane lipids during purification. In addition to a broad range of bacterial membrane proteins, OGDs also enable the purification and analysis of a functional G-protein coupled receptor (GPCR). Moreover, given the modular design of these detergents, we anticipate fine-tuning of their properties for specific applications in structural biology. Seen from a broader perspective, this represents a significant advance for the investigation of membrane proteins and their interactions with lipids.


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Rainer Haag, Carol V. Robinson, Kevin Pagel
Dec 16, 2019 mass spectra were aquired with Xcalibur Version 2.2 (Thermo Scientific), UV/VIS spectra were aquired using the software that is implemented in the commercial DeNovix UV/VIS photosprectrometer, NMR data and high-resolution mass spectrometry data for detergents and detergent precursors were received from the Corefacility BioSpuramol of the Freie Universität Berlin, dynamic light scattering data were collected using the Zetasizer Software Version 7.11 (Malvern), liquid chromatography data were aquired using ChromeGate Client Viewer Version 3.3.2 (Knauer), CD spectroscopy data were aqcuired using Pro-Data Chirascan V4.5 (Applied Photophysics), fluorescence spectroscopy data were aqcuired using CLARIOstar® V5.4 (BMG Labtech) mass spectra were analysed with Xcalibur version 2.2 (Thermo Scientific), ligand/lipid masses from mass spectra were calculated with Origin version 9.1 (OriginLab Corporation), mass spectra were processed with Unidec version 1.0.11, UV/VIS Data were read out manually and processed with Origin version 9.1 (OriginLab Corporation), NMR data were processed and analysed with MestReNova version 6.0.2-5475, exact masses of detergents and detergent precursors were calculated with ChemDraw version 14.0.0.117 (PerkinElmer) and compared to experimental values, dynamic light scattering data for critical aggregation concentration (cac) determination of our detergents were analysed with Origin version 9.1 (OriginLab Corporation), liquid chromatography data were analysed using ChromeGate Client Viewer Version 3.3.2 (Knauer), CD spectroscopy data were analyzed using Origin version 9.1 (OriginLab Corporation), fluorescence spectroscopy data were analyzed using MARS version 3.3 (BMG Labtech), and Origin version 9.1 (OriginLab Corporation)