(741a) Multiscale Modeling of Stratum Corneum Lipid Mixtures
AIChE Annual Meeting
2018 AIChE Annual Meeting
Engineering Sciences and Fundamentals
Thermophysical Properties of Biological Systems
Friday, November 2, 2018 - 8:00am to 8:25am
We present both atomistic and coarse-grained (CG) molecular dynamics simulations of simplified mixtures of SC lipids, namely cholesterol, free fatty acid, and ceramides. Atomistic simulations of pre-assembled bilayer structures are used to probe the impact of the individual lipid components on structure and examine the role of ceramide tail length . CG MD simulations are used to examine self-assembled structures that complement the atomistic studies. The CG force fields were parameterized using the multi-state and multi-ensemble iterative Boltzmann inversion method  based on simulation data from fully atomistic models . The CG results examine structural differences between bilayer and multilayer structures, and due to their computational efficiency, allow a larger range of parameters to be explored, including the role of free fatty acid chain length. The CG results also demonstrate that the intramolecular conformations of the ceramides are dependent on the lipid composition of the system, where increasing the number of lipid components gives rise to a greater fraction of extended ceramide conformations, helping to elucidate the 3D structure of these mixtures.
 Moore T.C., Hartkamp R., Iacovella C.R., Bunge A.L., McCabe C. The Influence of Ceramide Tail Length on the Structure of Bilayers Composed of Stratum Corneum Lipids, Biophysical Journal, 2018 114, 113-125
 Moore, T. C., Iacovella, C. R. & McCabe, C. Derivation of coarse-grained potentials via multistate iterative Boltzmann inversion. J. Chem. Phys. 2014, 140, 224104
 Moore, T. C., Iacovella, C. R., Hartkamp, R., Bunge, A. L. & McCabe, C. A Coarse-Grained Model of Stratum Corneum Lipids: Free Fatty Acids and Ceramide NS,â Journal of Physical Chemistry B, 120(37) 9944-9958 (2016).