Ling G N, Ochsenfeld M M
Biophys J. 1965 Nov;5(6):777-807. doi: 10.1016/S0006-3495(65)86752-2.
We studied the effect an alkali-metal ion exercised on the rate of entry of another alkali-metal ion into frog sartorius muscle cells and their models (i.e., ion exchange resin and sheep's wool). In the case of frog muscle, it was shown that the interaction fell into one of four categories; competition, facilitation, and two types of indifference. The observed pK value (4.6 to 4.7) of the surface anionic groups that combine with the alkali-metal ions suggests that they are beta- or gamma-carboxyl groups of proteins on the cell surface. The results were compared with four theoretical models which included three membrane models (continuous lipoid membrane with carrier; leaky membrane with carrier; membrane with fixed ionic sites) and one bulk-phase model. This comparison led to the conclusion that the only model that is self-consistent and agrees with all of the experimental facts is the one based on the concept that the entire living cell represents a proteinaceous fixed-charge system; this model correctly predicts all four types of interaction observed.
我们研究了一种碱金属离子对另一种碱金属离子进入青蛙缝匠肌细胞及其模型（即离子交换树脂和羊毛）的速率的影响。对于青蛙肌肉，结果表明这种相互作用可分为四类之一：竞争、促进以及两种无影响类型。与碱金属离子结合的表面阴离子基团的观测pK值（4.6至4.7）表明它们是细胞表面蛋白质的β-或γ-羧基。将结果与四个理论模型进行了比较，其中包括三个膜模型（带载体的连续脂质膜；带载体的漏膜；带固定离子位点的膜）和一个体相模型。这种比较得出的结论是，唯一自洽且与所有实验事实相符的模型是基于整个活细胞代表蛋白质固定电荷系统这一概念的模型；该模型正确地预测了观察到的所有四种相互作用类型。
