title: Bicelles and Other Membrane Mimics: Comparison of Structure, Properties, and Dynamics from MD Simulations.
abstract: The increased interest in studying membrane proteins has led to the development of new membrane mimics such as bicelles and nanodiscs. However, only limited knowledge is available of how these membrane mimics are affected by embedded proteins and how well they mimic a lipid bilayer. Herein, we present molecular dynamics simulations to elucidate structural and dynamic properties of small bicelles and compare them to a large alignable bicelle, a small nanodisc, and a lipid bilayer. Properties such as lipid packing and properties related to embedding both an α-helical peptide and a transmembrane protein are investigated. The small bicelles are found to be very dynamic and mainly assume a prolate shape substantiating that small bicelles cannot be regarded as well-defined disclike structures. However, addition of a peptide results in an increased tendency to form disc-shaped bicelles. The small bicelles and the nanodiscs show increased peptide solvation and difference in peptide orientation compared to embedding in a bilayer. The large bicelle imitated a bilayer well with respect to both curvature and peptide solvation, although peripheral binding of short tailed lipids to the embedded proteins is observed, which could hinder ligand binding or multimer formation.
authors.affiliation: Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University , Langelandsgade 140, DK-8000 Aarhus C, Denmark.
authors.forename: Mikkel
authors.initials: M
authors.lastname: Vestergaard
authors.affiliation: Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University , Langelandsgade 140, DK-8000 Aarhus C, Denmark.
authors.forename: Johan F
authors.initials: JF
authors.lastname: Kraft
authors.affiliation: Danish Center for Ultrahigh-Field NMR Spectroscopy and Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Vosegaard
authors.affiliation: Center for Membrane Pumps in Cells and Disease (PUMPKIN), Bioinformatics Research Centre, Aarhus University , C.F. Møllers Alle 8, DK-8000 Aarhus C, Denmark.
authors.forename: Lea
authors.initials: L
authors.lastname: Thøgersen
authors.affiliation: Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University , Langelandsgade 140, DK-8000 Aarhus C, Denmark.
authors.forename: Birgit
authors.initials: B
authors.lastname: Schiøtt
mesh_terms: D008051:Lipid Bilayers / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D008565:Membrane Proteins; D010455:Peptides