Durand M, Maurizot J C
Biochimie. 1980;62(7):503-7. doi: 10.1016/s0300-9084(80)80070-8.
The binding of lac repressor to poly d(A-T) and d(G-C) has been studied using circular dichroism. The results indicate that the binding induces the same conformational change of both polynucleotides and perturbs the same number of nucleic acid bases (28 bases). It is shown that in 0.1 M phosphate buffer the CD measurement can be used to determine the binding constant of lac repressor to poly d(A-T). Competition experiments performed at various salt concentrations show that the stronger interaction of lac repressor for poly d(A-T) than for poly d(G-C) is based on difference in the dissociation rate of the complexes whereas the association rate for both polymers are similar.
利用圆二色性研究了乳糖阻遏物与聚d(A - T)和d(G - C)的结合。结果表明，这种结合诱导了两种多核苷酸相同的构象变化，并扰动了相同数量的核酸碱基(28个碱基)。结果表明，在0.1 M磷酸盐缓冲液中，圆二色性测量可用于确定乳糖阻遏物与聚d(A - T)的结合常数。在不同盐浓度下进行的竞争实验表明，乳糖阻遏物与聚d(A - T)的相互作用比与聚d(G - C)的相互作用更强，这是基于复合物解离速率的差异，而两种聚合物的缔合速率相似。
