[NMR paper] Dicarboxylate-Oside Detergents for Extraction, Overstabilization and Crystallization of Membrane Proteins

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Dicarboxylate-Oside Detergents for Extraction, Overstabilization and Crystallization of Membrane Proteins


To tackle the problem of membrane proteins (MPs) instability in detergent solutions, we designed a series of dicarboxylate-oside detergents (DCODs) in which we optimized the polar head to clamp the membrane domain, including on one side a cluster of two carboxyl groups that promotes salt-bridges with basic residues abundant at the membrane-cytoplasm interface of MPs, and on the other side a sugar to generate H-bonds. Tested on BmrA, an ATP-binding cassette pump, DCODs 8b, 8c, and 9b preserved its ATPase function upon extraction much more efficiently than reference or recently designed detergents. DCOD 8b also conferred a long-range functional stability of DDM-purified BmrA of up to 40 days at 18 °C. DCODs 8(a,b,f) and 9(a,b) induced a thermal shift of 20 to 29°C for BmrA and of 13 to 21°C for the native version of the G-protein coupled adenosine receptor A2AR. The same proteins tested by size-exclusion chromatography with DCOD 8b behaved as with DDM. Finally, DCOD 8f and 8g improved the diffraction of BmrA crystals from 6 to 4 Å. These results make DCODs promising and powerful tools for the structural biology of MPs.

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