Abstract:
Lipid membranes are abundant in living organisms, where they constitute a surrounding shell for cells and their organelles. There are many circumstances in which the deformations of lipid membranes are involved in living cells: fusion and fission, membrane-mediated interaction between membrane inclusions, lipid-protein interaction, formation of pores, etc. In all of these cases, elastic parameters of lipid membranes are important for the description of membrane deformations, as these parameters determine energy barriers and characteristic times of membrane-involved phenomena. Since the development of molecular dynamics (MD), a variety of in silico methods have been proposed for the determination of elastic parameters of simulated lipid membranes. These MD methods allow for the consideration of details unattainable in experimental techniques and represent a distinct scientific field, which is rapidly developing. This work provides a review of these MD approaches with a focus on theoretical aspects. Two main challenges are identified: (i) the ambiguity in the transition from the continuum description of elastic theories to the discrete representation of MD simulations, and (ii) the determination of intrinsic elastic parameters of lipid mixtures, which is complicated due to the composition-curvature coupling effect.
摘要:
生物体内的脂膜含量丰富,它们构成细胞和细胞器的外壳。在许多情况下,脂质膜的变形与活细胞有关:融合和裂变,膜包裹体之间的膜介导相互作用,脂质-蛋白质相互作用,孔的形成,等。在所有这些情况下,脂质膜的弹性参数对于描述膜变形很重要,因为这些参数决定了能量屏障和膜相关现象的特征时间。自从分子动力学(MD)发展以来,已经提出了多种计算机模拟方法来确定模拟脂质膜的弹性参数。这些MD方法允许考虑实验技术中无法达到的细节,并代表了一个独特的科学领域。正在迅速发展。这项工作提供了对这些MD方法的回顾,重点是理论方面。确定了两个主要挑战:(i)从弹性理论的连续描述过渡到MD模拟的离散表示的歧义,和(ii)确定脂质混合物的内在弹性参数,这是复杂的,由于成分-曲率耦合效应。