title: Renaturing membrane proteins in the lipid cubic phase, a nanoporous membrane mimetic.
abstract: Membrane proteins play vital roles in the life of the cell and are important therapeutic targets. Producing them in large quantities, pure and fully functional is a major challenge. Many promising projects end when intractable aggregates or precipitates form. Here we show how such unfolded aggregates can be solubilized and the solution mixed with lipid to spontaneously self-assemble a bicontinuous cubic mesophase into the bilayer of which the protein, in a confined, chaperonin-like environment, reconstitutes with 100% efficiency. The test protein, diacylglycerol kinase, reconstituted in the bilayer of the mesophase, was then crystallized in situ by the in meso or lipid cubic phase method providing an X-ray structure to a resolution of 2.55 Å. This highly efficient, inexpensive, simple and rapid approach should find application wherever properly folded, membrane reconstituted and functional proteins are required where the starting material is a denatured aggregate.
authors: School of Biochemistry and Immunology & School of Medicine, Trinity College Dublin, Dublin, Ireland.
authors: Dianfan
authors: D
authors: Li
authors: School of Biochemistry and Immunology & School of Medicine, Trinity College Dublin, Dublin, Ireland.
authors: Martin
authors: M
authors: Caffrey
mesh_terms: D018360:Crystallography, X-Ray; D003902:Detergents / Q000737:chemistry; D019852:Diacylglycerol Kinase / Q000737:chemistry*; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry*; D018716:Molecular Mimicry; D049329:Nanostructures; D016062:Porosity; D058849:Protein Refolding; D012997:Solvents / Q000737:chemistry
chemical_list: D003902:Detergents; D029968:Escherichia coli Proteins; D008055:Lipids; D008565:Membrane Proteins; D012997:Solvents; D019852:Diacylglycerol Kinase