论文标题
从溶剂增强的接触值定理中对大分子相互作用的明确溶剂作用
Explicit Solvent Effects on Macromolecular Interactions From a Solvent-Augmented Contact Value Theorem
论文作者
论文摘要
Derjaguin-Landau-verywey-overbeek（DLVO）理论一直是水溶剂中大分子稳定性表征的一个非常准确的框架。鉴于其溶剂易于的性质忽略了具有不可忽略的电荷结构和浓度的水分子的静电，DLVO形式主义的精度有些令人困惑。为了阐明这个问题，我们源于早期的明确溶剂形式主义[S. buyukdagli el。，物理。 Rev. E，2013，87，063201]一个溶剂的接触值定理，并评估溶剂分子对带电膜相互作用的贡献。我们发现，在疏水膜的情况下，固定电荷嵌入在膜表面中，几乎精确地取消了基本大尺寸的各种显式溶剂效应，但相反的符号使膜间的压力显着接近DLVO理论的双层力量。然后，在水区域内的亲水表面电荷基团中，由于膜底物与固定电荷的位置的空间分离，在固定电荷的位置进行了结构化溶剂的非局部介电响应的位置，因此局部性场能和接触电荷密度不受explicitiit溶液的影响。结果，脂质头组的水合抑制了膜相互作用力的溶剂分子的特征。
The Derjaguin-Landau-Verywey-Overbeek (DLVO) theory has been a remarkably accurate framework for the characterization of macromolecular stability in water solvent. In view of its solvent-implicit nature neglecting the electrostatics of water molecules with non-negligible charge structure and concentration, the precision of the DLVO formalism is somewhat puzzling. In order to shed light on this issue, we derive from our earlier explicit solvent formalism [S. Buyukdagli el al., Phys. Rev. E, 2013, 87, 063201] a solvent-augmented contact value theorem and assess the contribution of solvent molecules to the interaction of charged membranes. We find that in the case of hydrophobic membranes with fixed charges embedded in the membrane surface, the nearly exact cancellation of various explicit solvent effects of substantially large magnitude but opposite sign keeps the intermembrane pressure significantly close to the double layer force of the DLVO theory. Then, in the case of hydrophilic surface charge groups within the aqueous region, due to the spatial separation of the membrane substrate from the location of the fixed charges where the non-local dielectric response of the structured solvent is sharply localized, the interfacial field energy and the contact charge densities remain unaffected by the explicit solvent. As a result, the hydration of the lipid head groups suppresses the signature of the solvent molecules from the membrane interaction force.
