Dahirel Vincent, Jardat Marie, Dufrêche Jean-François, Turq Pierre
Université Pierre et Marie Curie-Paris 6, Laboratoire Liquides Ioniques et Interfaces Chargées, UMR CNRS 7612, Case Courrier 51, 4 Place Jussieu 75005 Paris, France.
J Chem Phys. 2007 Sep 7;127(9):095101. doi: 10.1063/1.2767626.
Monte Carlo simulations are used to calculate the exact potential of mean force between charged globular proteins in aqueous solution. The aim of the present paper is to study the influence of the ions of the added salt on the effective interaction between these nanoparticles. The charges of the model proteins, either identical or opposite, are either central or distributed on a discrete pattern. Contrarily to Poisson-Boltzmann predictions, attractive, and repulsive direct forces between proteins are not screened similarly. Moreover, it has been shown that the relative orientations of the charge patterns strongly influence salt-mediated interactions. More precisely, for short distances between the proteins, ions enhance the difference of the effective forces between (i) like-charged and oppositely charged proteins, (ii) attractive and repulsive relative orientations of the proteins, which may affect the selectivity of protein/protein recognition. Finally, such results observed with the simplest models are applied to a more elaborate one to demonstrate their generality.
蒙特卡罗模拟用于计算水溶液中带电球状蛋白质之间平均力的精确势能。本文的目的是研究添加盐的离子对这些纳米颗粒之间有效相互作用的影响。模型蛋白质的电荷可以相同或相反，要么集中在中心，要么以离散模式分布。与泊松 - 玻尔兹曼预测相反，蛋白质之间的吸引和排斥直接力的屏蔽方式并不相同。此外，已经表明电荷模式的相对取向强烈影响盐介导的相互作用。更确切地说，对于蛋白质之间的短距离，离子增强了（i）同种电荷和异种电荷蛋白质之间、（ii）蛋白质的吸引和排斥相对取向之间有效力的差异，这可能会影响蛋白质/蛋白质识别的选择性。最后，将用最简单模型观察到的这些结果应用于更复杂的模型以证明其普遍性。
