Knack I, Röhm K H
Biochim Biophys Acta. 1980 Aug 7;614(2):613-24. doi: 10.1016/0005-2744(80)90251-x.
A fitting method for saturation curves is described that may be applied to any kind of ligand binding process, regardless of whether positive, negative or mixed cooperativity is involved. The procedure yields 'best values' of maximal saturation (or maximal velocity with enzymes); in addition, an empirical function is calculated that represents the concentration dependence of the Hill slope (i.e. the slope of the corresponding Hill plot). Since the method does not require the maximal saturation to be known in advance, it can be successfully applied to systems which, due to experimental limitations, may not be saturated with ligand. It is shown that in these cases values of maximal saturation are obtained that are considerably more reliable than those estimated by customary methods. Moreover, it is demonstrated that the concentration dependence of the Hill slope, the other main result of the proposed procedure, may offer useful evidence as to the molecular events leading to non-hyperbolicity and thus provide a rational basis for selecting more specific models to describe the properties of the system studied.
本文描述了一种适用于饱和曲线的拟合方法，该方法可应用于任何类型的配体结合过程，无论涉及正协同性、负协同性还是混合协同性。该程序可得出最大饱和度（或酶的最大速度）的“最佳值”；此外，还计算了一个经验函数，该函数表示希尔斜率的浓度依赖性（即相应希尔图的斜率）。由于该方法不需要预先知道最大饱和度，因此它可以成功应用于由于实验限制可能未被配体饱和的系统。结果表明，在这些情况下获得的最大饱和度值比用传统方法估计的要可靠得多。此外，本文还证明，希尔斜率的浓度依赖性作为所提出程序的另一个主要结果，可能为导致非双曲线性的分子事件提供有用的证据，从而为选择更具体的模型来描述所研究系统的性质提供合理依据。
