title: A coarse-grained MARTINI model of polyethylene glycol and of polyoxyethylene alkyl ether surfactants.
abstract: Nonionic surfactants are used for the isolation and purification of membrane proteins, as well as for the study of fundamental aspects of protein diffusion in membranes. Here we present a new coarse-grained model of polyethylene glycol (PEG) and of the family of polyoxyethylene alkyl ether (C(i)E(j)) surfactants. The model is compatible with the MARTINI coarse-grained force-field for lipids and proteins. We validate the model by comparing molecular dynamics simulations with experimental data. In particular, we show that the model reproduces the phase behavior of water-surfactant mixtures as a function of water concentration. We also simulate the self-assembly of two ternary mixtures that have been used for the experimental measure of protein diffusion coefficients. The first includes a cosurfactant that affects the curvature of the surfactant bilayers; the second is a mixture of C(i)E(j) surfactants, alkanes and water. In both cases, the results of self-assembly simulations are in agreement with experimental observations and pave the way to the use of the surfactant model in combination with MARTINI peptides and proteins.
authors.affiliation: INSERM, UMR-S665, Paris, F-75015, France. giulia.rossi@gmail.com
authors.forename: G
authors.initials: G
authors.lastname: Rossi
authors.forename: P F J
authors.initials: PF
authors.lastname: Fuchs
authors.forename: J
authors.initials: J
authors.lastname: Barnoud
authors.forename: L
authors.initials: L
authors.lastname: Monticelli
mesh_terms: D004058:Diffusion; D056004:Molecular Dynamics Simulation; D011092:Polyethylene Glycols / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry*; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D011506:Proteins; C495681:Sanonic SS-90; D013501:Surface-Active Agents; D014867:Water; D011092:Polyethylene Glycols