Lagüe P, Zuckermann M J, Roux B
Department of Physics, Université de Montréal, Québec, Canada.
Faraday Discuss. 1998(111):165-72; discussion 225-46. doi: 10.1039/a807109h.
A theory for describing the structure of the hydrocarbon chains around a protein inclusion embedded in a lipid bilayer is developed on the basis of the hypernetted chain integral equation formalism for liquids. The exact lateral density-density response function of the hydrocarbon core, which is extracted from a molecular dynamics simulation of a pure lipid bilayer, is used as input to the theory. Numerical calculations show that the average lipid order is perturbed over a distance of 25 to 30 A around a hard repulsive cylinder of 5 A radius representing an alpha-helical polyleucine protein inclusion. The lipid-mediated protein-protein interaction is calculated and is shown to be non-monotonic, being repulsive at an intermediate range but attractive at short range. It is found that the lipid matrix contributes a free energy well of 8 kBT to the association of two cylindrical inclusions.
基于液体的超网链积分方程形式，建立了一种描述嵌入脂质双层中的蛋白质内含物周围烃链结构的理论。从纯脂质双层的分子动力学模拟中提取的烃核精确横向密度-密度响应函数用作该理论的输入。数值计算表明，在半径为5 Å的硬排斥圆柱体（代表α-螺旋聚亮氨酸蛋白质内含物）周围25至30 Å的距离内，平均脂质有序性受到扰动。计算了脂质介导的蛋白质-蛋白质相互作用，结果表明其是非单调的，在中间范围内是排斥的，但在短范围内是吸引的。研究发现，脂质基质对两个圆柱形内含物的缔合贡献了8 kBT的自由能阱。
