den Otter W K, Shkulipa S A
Computational Biophysics, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
Biophys J. 2007 Jul 15;93(2):423-33. doi: 10.1529/biophysj.107.105395. Epub 2007 Apr 27.
The flow behavior of lipid bilayer membranes is characterized by a surface viscosity for in-plane shear deformations, and an intermonolayer friction coefficient for slip between the two leaflets of the bilayer. Both properties have been studied for a variety of coarse-grained double-tailed model lipids, using equilibrium and nonequilibrium molecular dynamics simulations. For lipids with two identical tails, the surface shear viscosity rises rapidly with tail length, while the intermonolayer friction coefficient is less sensitive to the tail length. Interdigitation of lipid tails across the bilayer midsurface, as observed for lipids with two distinct tails, strongly enhances the intermonolayer friction coefficient, but hardly affects the surface shear viscosity. The simulation results are compared against the available experimental data.
平面内剪切变形的表面粘度,以及双层膜两个小叶之间滑动的层间摩擦系数。使用平衡和非平衡分子动力学模拟,对多种粗粒化双尾模型脂质的这两种特性进行了研究。对于具有两条相同尾巴的脂质,表面剪切粘度随尾巴长度迅速增加,而层间摩擦系数对尾巴长度不太敏感。如在具有两条不同尾巴的脂质中观察到的那样,脂质尾巴跨双层中间表面的交错排列强烈增强了层间摩擦系数,但几乎不影响表面剪切粘度。将模拟结果与现有的实验数据进行了比较。