Use of binding site neighbor-effect parameters to evaluate the interactions between adjacent ligands on a linear lattice. Effects on ligand-lattice association.
Use of binding site neighbor-effect parameters to evaluate the interactions between adjacent ligands on a linear lattice. Effects on ligand-lattice association.
复制标题
使用结合位点邻近效应参数来评估线性晶格上相邻配体之间的相互作用。
DOI：
10.1016/0022-2836(92)90262-i
复制
发表时间：
1992
影响因子：
5.6
通讯作者：
Meehan,T
中科院分区：
文献类型：
--
作者：
Wolfe,AR;Meehan,T
介绍了一种利用结合位点“邻体效应”参数（NEPs）来评价相邻配体间相互作用对它们与无限线性晶格结合的影响的方法。结合位点重叠也被考虑在内。这使得McGhee和von Hippel的条件概率方法可以扩展到更复杂的情况。等温线的一般方程是ν L F= S F K F，其中ν是结合配体与晶格残基的比率，L F是游离配体浓度，S F是游离结合位点的分数，K F是游离位点的平均缔合常数。解决方案推导出三种情况下：对称配体，和各向同性或各向异性晶格上的不对称配体。对于对称配体，存在一个NEP，E，其是如果邻近位点一端的晶格残基的状态未指定（随机），则游离位点的平均结合亲和力与该残基游离时的亲和力（保持另一个相邻残基恒定）的比率。因此，K = F是KE 2，其中K是分离位点的亲和力。如果一个位点的长度是n个残基，则SF是f ff n− 1，其中f= 1− n是自由残基的分数，ff是自由残基在给定侧与另一个自由残基邻接的条件概率。ff的表达式是1（1+ x/E），其中x是ν f，E是（1− x+[（1− x）2+ 4xω）] 1 2）/2，ω是协同性参数。非对称配体的各向同性晶格的结合是由两个NEPs描述的，最后一种情况涉及四个NEPs和一个绑定配体取向参数。对于每种情况，结合配体簇的预期长度分布可以作为ν的函数计算。当Scatchard图与相同的截距和初始斜率进行比较，它被发现，配体不对称降低等温线（相对于相应的对称配体等温线），而晶格各向异性提高它。
A method using binding site “neighbor-effect” parameters (NEPs) is introduced to evaluate the effects of interaction between adjacent ligands on their binding to an infinite linear lattice. Binding site overlap is also taken into account. This enables the conditional probability approach of McGhee & von Hippel to be extended to more complex situations. The general equation for the isotherm is ν L F= S F K F, where ν is the ratio of bound ligands to lattice residues, L F is the free ligand concentration, S F is the fraction of binding sites that are free, and K̄ F is the average association constant of a free site. Solutions are derived for three cases: symmetric ligands, and asymmetric ligands on isotropic or anisotropic lattices. For symmetric ligands there is one NEP, E, which is the ratio of the average binding affinity of a free site if the status of the lattice residue neighboring one end of the site is unspecified (left to chance) to the affinity when this residue is free (holding the other neighbor constant). Thus K̄ F is KE 2, where K is the affinity of an isolated site. If a site is n residues long, S F is f ff n− 1, where f= 1− nv is the fraction of residues that are free and ff is the conditional probability that a free residue is bordered on a given side by another free residue. The expression for ff is 1 (1+ x/E), where x is ν f, E is (1− x+[(1− x) 2+ 4xω)] 1 2)/2, and ω is the co-operativity parameter. The binding of asymmetric ligands to an isotropic lattice is described by two NEPs; the last case involves four NEPs and a bound ligand orientation parameter. For each case, the expected length distribution of clusters of bound ligands can be calculated as a function of ν. When Scatchard plots with the same intercepts and initial slope are compared, it is found that ligand asymmetry lowers the isotherm (relative to the corresponding symmetric ligand isotherm), whereas lattice anisotropy raises it.
登录
查看更多内容
影响因子：
1.2
作者：
Nechipurenko IuD
通讯作者：
Nechipurenko IuD
影响因子：
2.9
作者：
CROTHERS, DM
通讯作者：
CROTHERS, DM
奎纳克林与 DNA 相互作用的协同性和离子效应分析
影响因子：
2.9
作者：
W. Wilson;I. Lopp
通讯作者：
I. Lopp
蛋白质-核酸协同结合的热力学和动力学。
影响因子：
5.6
作者：
G. Schwarz;F. Watanabe
通讯作者：
F. Watanabe
球芽孢杆菌 HB 蛋白与核酸的相互作用。
DOI：
--
发表时间：
1984
期刊：
European Journal of Biochemistry
影响因子：
--
作者：
F. Watanabe;S. Stankowski;G. Schwarz
通讯作者：
G. Schwarz