Pandit Sagar A, Scott H Larry
Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA.
J Chem Phys. 2006 Jan 7;124(1):14708. doi: 10.1063/1.2140689.
Ceramide is the simplest lipid in the biologically important class of glycosphingolipids. Ceramide is an important signaling molecule and a major component of the strateum corneum layer in the skin. In order to begin to understand the biophysical properties of ceramide, we have carried out a molecular-dynamics simulation of a hydrated 16:0 ceramide lipid bilayer at 368 K (5 degrees above the main phase transition). In this paper we describe the simulation and present the resulting properties of the bilayer. We compare the properties of the simulated ceramide bilayer to an earlier simulation of 18:0 sphingomyelin, and we discuss the results as they relate to experimental data for ceramide and other sphingolipids. The most significant differences arise at the lipid/water interface, where the lack of a large ceramide polar group leads to a different electron density and a different electrostatic potential but, surprisingly, not a different overall "dipole potential," when ceramide is compared to sphingomyelin.
神经酰胺是生物重要的糖鞘脂类中最简单的脂质。神经酰胺是一种重要的信号分子，也是皮肤角质层的主要成分。为了开始理解神经酰胺的生物物理性质，我们在368 K（比主相变温度高5摄氏度）下对水合16:0神经酰胺脂质双层进行了分子动力学模拟。在本文中，我们描述了该模拟并展示了双层的所得性质。我们将模拟的神经酰胺双层的性质与早期对18:0鞘磷脂的模拟进行了比较，并讨论了与神经酰胺和其他鞘脂的实验数据相关的结果。最显著的差异出现在脂质/水界面，与鞘磷脂相比，神经酰胺缺乏大的极性基团导致不同的电子密度和不同的静电势，但令人惊讶的是，整体“偶极势”并无差异。
