Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON, Canada; Department of Physics, University of Windsor, Windsor, ON, Canada.
Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA.
Chem Phys Lipids. 2020 Jul;229:104892. doi: 10.1016/j.chemphyslip.2020.104892. Epub 2020 Feb 12.
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 Å and 70.4 Å for PDPC and SDPC bilayers, respectively, and a model free analysis of PDPC at 30 °C resulted in a lipid area of 72 Å. In addition to bilayer structural parameters, using area-constrained MD simulations we determined the area compressibility modulus, K, to be 246.4 mN/m, a value similar to other neutral phospholipids.
我们展示了多不饱和脂肪酸磷脂，即 1-棕榈酰基-2-二十二碳六烯酰基-sn-甘油-3-磷酸胆碱（PDPC）和 1-硬脂酰基-2-二十二碳六烯酰基-sn-甘油-3-磷酸胆碱（SDPC）的详细结构分析。我们将一种新开发的含有多个双键脂肪酸的分子动力学（MD）模拟解析方案应用于散射密度剖面（SDP）模型，以同时细化具有不同对比度的中子和 X 射线散射数据。在 30°C 下对散射数据进行 SDP 分析，得出 PDPC 和 SDPC 双层的脂质面积分别为 71.1Å 和 70.4Å，30°C 下的 PDPC 无模型分析得出的脂质面积为 72Å。除了双层结构参数外，我们还通过面积约束 MD 模拟确定了面积压缩模量 K 为 246.4 mN/m，这与其他中性磷脂的值相似。
