Marrink S J, Mark A E
Department of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Biochemistry. 2002 Apr 30;41(17):5375-82. doi: 10.1021/bi015613i.
Extensive molecular dynamics (MD) simulations of binary systems of phospholipids and bile salts, a model for human bile, have been performed. Recent progress in hardware and software development allows simulation of the spontaneous aggregation of the constituents into small mixed micelles, in agreement with experimental observations. The MD simulations reveal the structure of these micelles at atomic detail. The phospholipids are packed radially with their headgroups at the surface and the hydrophobic tails pointing toward the micellar center. The bile salts act as wedges between the phospholipid headgroups, with their hydrophilic sides exposed to the aqueous environment. The structure of the micelles strongly resembles the previously proposed radial shell model. Simulations including small fractions of cholesterol reveal how cholesterol is solubilized inside these mixed micelles without changing their overall structure.
已对磷脂和胆汁盐的二元体系进行了广泛的分子动力学（MD）模拟，该体系是人类胆汁的模型。硬件和软件开发的最新进展使得能够模拟成分自发聚集形成小的混合微团，这与实验观察结果一致。MD模拟揭示了这些微团在原子细节上的结构。磷脂以其头部基团在表面、疏水尾部指向微团中心的方式呈放射状排列。胆汁盐作为磷脂头部基团之间的楔子，其亲水侧暴露于水环境中。微团的结构与先前提出的放射状壳层模型非常相似。包含少量胆固醇的模拟揭示了胆固醇如何在不改变这些混合微团整体结构的情况下溶解在其中。
