Tourdot Richard W, Ramakrishnan N, Baumgart Tobias, Radhakrishnan Ravi
Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Oct;92(4):042715. doi: 10.1103/PhysRevE.92.042715. Epub 2015 Oct 29.
We investigate the phenomenon of protein-induced tubulation of lipid bilayer membranes within a continuum framework using Monte Carlo simulations coupled with the Widom insertion technique to compute excess chemical potentials. Tubular morphologies are spontaneously formed when the density and the curvature-field strength of the membrane-bound proteins exceed their respective thresholds and this transition is marked by a sharp drop in the excess chemical potential. We find that the planar to tubular transition can be described by a micellar model and that the corresponding free-energy barrier increases with an increase in the curvature-field strength (i.e., of protein-membrane interactions) and also with an increase in membrane tension.
我们在连续介质框架内，使用蒙特卡罗模拟结合维道姆插入技术来计算过量化学势，研究了蛋白质诱导脂质双分子层膜形成微管的现象。当膜结合蛋白的密度和曲率场强度超过各自的阈值时，管状形态会自发形成，并且这种转变以过量化学势的急剧下降为标志。我们发现，从平面到管状的转变可以用胶束模型来描述，并且相应的自由能垒会随着曲率场强度（即蛋白质 - 膜相互作用）的增加以及膜张力的增加而增大。
