Chemistry and Physics of Lipids
MD simulations, Neutron scattering, Polyunsaturated fatty acids, X-ray scattering
© 2020 Elsevier B.V. We present the detailed structural analysis of polyunsaturated fatty acid-containing phospholipids namely, 1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (PDPC) and 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (SDPC). A newly developed molecular dynamics (MD) simulation parsing scheme for lipids containing fatty acids with multiple double bonds was implemented into the scattering density profile (SDP) model to simultaneously refine differently contrasted neutron and X-ray scattering data. SDP analyses of scattering data at 30 °C yielded lipid areas of 71.1 Å2 and 70.4 Å2 for PDPC and SDPC bilayers, respectively, and a model free analysis of PDPC at 30 °C resulted in a lipid area of 72 Å2. In addition to bilayer structural parameters, using area-constrained MD simulations we determined the area compressibility modulus, KA, to be 246.4 mN/m, a value similar to other neutral phospholipids.
Marquardt, Drew; Heberle, Frederick A.; Pan, Jianjun; Cheng, Xiaolin; Pabst, Georg; Harroun, Thad A.; Kučerka, Norbert; and Katsaras, John. (2020). The structures of polyunsaturated lipid bilayers by joint refinement of neutron and X-ray scattering data. Chemistry and Physics of Lipids, 229.