Milik M, Skolnick J
Department of Molecular Biology, Scripps Research Institute, La Jolla, CA 92037.
Proc Natl Acad Sci U S A. 1992 Oct 15;89(20):9391-5. doi: 10.1073/pnas.89.20.9391.
The Monte Carlo dynamics method was used to examine the process of protein insertion into model cell membranes. The water and lipid environments were taken into account via an effective medium approximation based on coordinate-dependent hydrophobic and hydrogen bond potentials. The polypeptide chain was represented in a full-backbone atom representation as a chain of diamond lattice vectors. The simulations support the idea that to a good approximation insertion may be depicted as a spontaneous thermodynamic process. The mechanism of membrane insertion of a simple lattice protein chain exhibits many features of theoretical predictions and is in good accord with experimental data. In the model, insertion begins with adsorption of the chain onto the interface, followed by the formation of helical fragments. These fragments, having partially saturated internal hydrogen bonds, can be transported into the lipid phase and then form transbilayer structures.
采用蒙特卡罗动力学方法研究蛋白质插入模型细胞膜的过程。基于坐标依赖的疏水和氢键势，通过有效介质近似考虑水和脂质环境。多肽链以全骨架原子表示法表示为菱形晶格向量链。模拟结果支持这样一种观点，即插入过程在良好近似下可被描述为一个自发的热力学过程。简单晶格蛋白质链的膜插入机制展现出许多理论预测的特征，并且与实验数据高度吻合。在该模型中，插入过程始于链在界面上的吸附，随后形成螺旋片段。这些片段部分饱和了内部氢键，能够被转运到脂质相中，然后形成跨膜结构。
