We present an extension of the Martini coarse-grained force field to glycolipids. The glycolipids considered here are the glycoglycerolipids monogalactosyldiacylglycerol (MGDG), sulfoquinovosyldiacylglycerol (SQDG), digalactosyldiacylglycerol (DGDG), and phosphatidylinositol (PI) and its phosphorylated forms (PIP, PIP2), as well as the glycosphingolipids galactosylceramide (GCER) and monosialotetrahexosylganglioside (GM1). The parametrization follows the same philosophy as was used previously for lipids, proteins, and carbohydrates focusing on the reproduction of partitioning free energies of small compounds between polar and nonpolar solvents. Bonded parameters are optimized by comparison to lipid conformations sampled with an atomistic force field, in particular with respect to the representation of the most populated states around the glycosidic linkage. Simulations of coarse-grained glycolipid model membranes show good agreement with atomistic simulations as well as experimental data available, especially concerning structural properties such as electron densities, area per lipid, and membrane thickness. Our coarse-grained model opens the way to large scale simulations of biological processes in which glycolipids are important, including recognition, sorting, and clustering of both external and membrane bound proteins.

Faculty of Science University of South Bohemia Czech Republic and Institute of Nanobiology and Structural Biology GCRC ASCR v v i Nove Hrady Czech Republic

Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials University of Groningen Nijenborgh 7 9747 AG Groningen The Netherlands

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Computational Methods for Modeling Lipid-Mediated Active Pharmaceutical Ingredient Delivery

Martini 3: a general purpose force field for coarse-grained molecular dynamics