Smirnova Y G, Müller M
Institute for Theoretical Physics, Georg-August-Universität, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany.
J Chem Phys. 2015 Dec 28;143(24):243155. doi: 10.1063/1.4938383.
The free-energy change of membrane shape transformations can be small, e.g., as in the case of membrane bending. Therefore, the calculation of the free-energy difference between different membrane morphologies is a challenge. Here, we discuss a computational method - field-theoretic umbrella sampling - to compute the local chemical potential of a non-equilibrium configuration and illustrate how one can apply it to study free-energy changes of membrane transformations using simulations. Specifically, the chemical potential profile of the bent membrane and the bending rigidity of membrane are calculated for a soft, coarse-grained amphiphile model and the MARTINI model of a dioleoylphosphatidylcholine (DOPC) membrane.
膜形状转变的自由能变化可能很小，例如在膜弯曲的情况下。因此，计算不同膜形态之间的自由能差是一项挑战。在这里，我们讨论一种计算方法——场论伞形抽样——来计算非平衡构型的局部化学势，并说明如何使用模拟将其应用于研究膜转变的自由能变化。具体而言，针对软的、粗粒化的两亲分子模型和二油酰磷脂酰胆碱（DOPC）膜的MARTINI模型，计算了弯曲膜的化学势分布和膜的弯曲刚度。
