Horiike K, Shiga K, Isomoto A, Yamano T
J Biochem. 1977 Jan;81(1):179-86. doi: 10.1093/oxfordjournals.jbchem.a131433.
We have mathematically analyzed ligand-induced monomerization and dimerization in a protein monomer-dimer equilibrium system, in which the monomer has one and the dimer two binding sites. These dimer sites have the same binding constants for the first ligand but may cooperatively interact when one of them is occupied by a ligand molecule. In this system, the apparent dimerization constant and the apparent molecular weight are functions of free ligand concentration, and depend on the intrinsic binding constants of the ligand molecule to the monomer and the dimer. The behavior of these functions is classified into 17 cases according to the values of the three intrinsic binding constants, and some calculated examples are shown graphically for selected parameters. The theory was also applied to D-amino acid oxidase [EC 1.4.3.3], a flavoprotein, and the pH dependence of the apparent dimerization constant and the apparent molecular weight in the presence of ligand, p-aminobenzoate, were studied theoretically using parameters obtained in our previous experiments (5).
我们对蛋白质单体 - 二聚体平衡系统中配体诱导的单体化和二聚化进行了数学分析，其中单体有一个结合位点，二聚体有两个结合位点。这些二聚体位点对第一个配体具有相同的结合常数，但当其中一个被配体分子占据时可能会协同相互作用。在这个系统中，表观二聚化常数和表观分子量是游离配体浓度的函数，并且取决于配体分子与单体和二聚体的固有结合常数。根据三个固有结合常数的值，这些函数的行为被分为17种情况，并针对选定的参数以图形方式展示了一些计算示例。该理论还应用于黄素蛋白D - 氨基酸氧化酶[EC 1.4.3.3]，并使用我们之前实验（5）中获得的参数从理论上研究了在配体对氨基苯甲酸存在下表观二聚化常数和表观分子量对pH的依赖性。
