College of Chemistry, Chemical Engineering, and Materials Science, Soochow University, Suzhou 215123, China.
J Phys Chem B. 2010 Sep 30;114(38):12183-92. doi: 10.1021/jp1039207.
Molecular dynamics simulations have been performed on three transmembrane cyclic peptide nanotubes, i.e., 8 × (WL)(n=3,4,5)/POPE (with uniform lengths but various radii) to investigate the radial dependences of the water-chain structures, diffusions, and transportation properties. The diffusions of individual water molecules and collective coordinates of all the channel-water in the three systems are certified as unbiased Brownian motions. From the very good linear relationships between MSDs and time intervals, the diffusion coefficients and transportation permeabilities have been deduced efficiently. Under the hydrostatic pressure differences across the membrane, a net unidirectional water flow rose up, and the osmotic permeabilities were determined. The ratios of the osmotic and diffusion permeabilities (p(f)/p(d)) were examined for all the three channels.
我们对三个跨膜环状多肽纳米管进行了分子动力学模拟，即 8×(WL)(n=3,4,5)/POPE（具有相同的长度但不同的半径），以研究水链结构、扩散和传输性质的径向依赖性。三个体系中单个水分子的扩散和所有通道水的集体坐标都被证明是无偏的布朗运动。从 MSDs 和时间间隔之间非常好的线性关系，可以有效地推导出扩散系数和传输渗透率。在跨膜的静水压力差下，产生了净单向水流，并且测定了渗透渗透率。对于所有三个通道，都检查了渗透渗透率和扩散渗透率的比值（p(f)/p(d)）。
