论文标题
镁离子与生物聚合物相互作用的平均场理论：溶菌酶的情况
Mean-field theory of the Interaction of the Magnesium Ion with Biopolymers: The Case of Lysozyme
论文作者
论文摘要
在后者带正电的条件下，镁离子与溶菌酶相互作用提出了统计理论。暂时假设镁与蛋白质无共价结合，我以扰动方式准确而均匀地求解非线性泊松托管方程。由于过度拍摄的，其有效电荷的结果表达比名义大，它是微妙的，不能在实用的高离子强度下渐近地扩展。然后将可能的粘合剂与可能结合的镁的假设获得的粘合电位与Tessier等人的第二个病毒系数的测量相符。与光密度测量值相比，与MGBR2浓度的函数相比，结合镁离子的数量是完全合理的。
A statistical theory is presented of the magnesium ion interacting with lysozyme under conditions where the latter is positively charged. Temporarily assuming magnesium is not noncovalently bound to the protein, I solve the nonlinear Poisson-Boltzmann equation accurately and uniformly in a perturbative fashion. The resulting expression for the effective charge, which is larger than nominal owing to overshooting, is subtle and cannot be asymptotically expanded at high ionic strengths that are practical. An adhesive potential taken from earlier work together with the assumption of possibly bound magnesium is then fitted to be in accord with measurements of the second virial coefficient by Tessier et al. The resulting numbers of bound magnesium ions as a function of MgBr2 concentration are entirely reasonable compared with densitometry measurements.
