Venable R M, Zhang Y, Hardy B J, Pastor R W
Biophysics Laboratory, Food and Drug Administration, Bethesda, MD 20892.
Science. 1993 Oct 8;262(5131):223-6. doi: 10.1126/science.8211140.
Molecular dynamics simulations of a fluid-phase dipalmitoyl phosphatidylcholine lipid bilayer in water and of neat hexadecane are reported and compared with nuclear magnetic resonance spin-lattice relaxation and quasi-elastic neutron scattering data. On the 100-picosecond time scale of the present simulations, there is effectively no difference in the reorientational dynamics of the carbons in the membrane interior and in pure hexadecane. Given that the calculated fast reorientational correlation times and the "microscopic" lateral diffusion of the lipids show excellent agreement with the experimental results, it is concluded that the apparently high viscosity of the membrane is more closely related to molecular interactions on the surface rather than in the interior.
本文报道了水相中二棕榈酰磷脂酰胆碱脂质双层以及纯十六烷的分子动力学模拟结果，并将其与核磁共振自旋晶格弛豫和准弹性中子散射数据进行了比较。在当前模拟的100皮秒时间尺度上，膜内部的碳原子与纯十六烷中的碳原子在重取向动力学上实际上没有差异。鉴于计算得到的快速重取向相关时间以及脂质的“微观”横向扩散与实验结果显示出极好的一致性，得出的结论是，膜表面明显较高的粘度与表面而非内部的分子相互作用更密切相关。
