Mechanics of water pore formation in lipid membrane under electric field  

作　　者：Bing Bu Dechang Li Jiajie Diao Baohua Ji 

机构地区：[1]Biomechanics and Biomaterials Laboratory,Department of Applied Mechanics,Beijing Institute of Technology [2]Department of Cancer Biology,College of Medicine,University of Cincinnati

出　　处：《Acta Mechanica Sinica》2017年第2期234-242,共9页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grants 11372042, 11221202, 11532009, and 11202026)

摘　　要：Transmembrane water pores are crucial for substance transport through cell membranes via membrane fusion, such as in neural communication. However, the molecular mechanism of water pore formation is not clear. In this study, we apply all-atom molecular dynamics and bias-exchange metadynamics simulations to study the process of water pore formation under an electric field. We show that water molecules can enter a membrane under an electric field and form a water pore of a few nanometers in diameter. These water molecules disturb the interactions between lipid head groups and the ordered arrangement of lipids. Following the movement of water molecules, the lipid head groups are rotated and driven into the hydrophobic region of the membrane. The reorientated lipid head groups inside the membrane form a hydrophilic surface of the water pore. This study reveals the atomic details of how an electric field influences the movement of water molecules and lipid head groups, resulting in water pore formation.Transmembrane water pores are crucial for substance transport through cell membranes via membrane fusion, such as in neural communication. However, the molecular mechanism of water pore formation is not clear. In this study, we apply all-atom molecular dynamics and bias-exchange metadynamics simulations to study the process of water pore formation under an electric field. We show that water molecules can enter a membrane under an electric field and form a water pore of a few nanometers in diameter. These water molecules disturb the interactions between lipid head groups and the ordered arrangement of lipids. Following the movement of water molecules, the lipid head groups are rotated and driven into the hydrophobic region of the membrane. The reorientated lipid head groups inside the membrane form a hydrophilic surface of the water pore. This study reveals the atomic details of how an electric field influences the movement of water molecules and lipid head groups, resulting in water pore formation.

关 键 词：Cell membrane Membrane fusion Water pore formation Electric field Molecular dynamics simulation 

分 类 号：Q61[生物学—生物物理学]