title: Characterization of fast-tumbling isotropic bicelles by PFG diffusion NMR.
abstract: Small isotropic bicelles are versatile membrane mimetics, which, in contrast to micelles, provide a lipid bilayer and are at the same time suitable for solution-state NMR studies. The lipid composition of the bilayer is flexible allowing for incorporation of various head groups and acyl chain types. In bicelles, lipids are solubilized by detergents, which are localized in the rim of the disk-shaped lipid bilayer. Bicelles have been characterized by a broad array of biophysical methods, pulsed-field gradient NMR (PFG NMR) being one of them. PFG NMR can readily be used to measure diffusion coefficients of macromolecules. It is thus employed to characterize bicelle size and morphology. Even more importantly, PFG NMR can be used to study the degree of protein association to membranes. Here, we present the advances that have been made in producing small, fast-tumbling isotropic bicelles from a variety of lipids and detergents, together with insights on the morphology of such mixtures gained from PFG NMR. Furthermore, we review approaches to study protein-membrane interaction by PFG NMR. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
authors.forename: Jobst
authors.initials: J
authors.lastname: Liebau
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
authors.forename: Weihua
authors.initials: W
authors.lastname: Ye
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Mäler
mesh_terms: D004058:Diffusion; D008051:Lipid Bilayers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008563:Membrane Lipids / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry; D008823:Micelles; D011485:Protein Binding; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D008563:Membrane Lipids; D008565:Membrane Proteins; D008823:Micelles
keywords: bilayer association; detergent; diffusion; lipid; membrane mimetics; morphology