Nechipurenko Iu D, Riabokon' V F, Semenov S V, Evdokimov Iu M
Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, ul. Vavilova 32, Moscow, 119991 Russia.
Biofizika. 2003 Jul-Aug;48(4):635-43.
Three variants of the model for the formation of "bridges" between the nucleic acid molecules fixed in the structure of particles of liquid-crystalline dispersions were considered. What the three variants have in common is that the bridges represent polymeric chelate cross-links consisting of alternating molecules of daunomycin and copper ions. The differences between the three variants are that in the first variant, the bridges begin and end with daunomycin molecules that form a complex by the mechanism of external binding with nucleic acids; in the second variant, the bridges begin and end with copper ions coupled with the pairs of bases of nucleic acids; and in the third variant, the bridges begin with the daunomycin molecule and end with the copper ion. For each variant, a mathematical model was constructed, which describes the formation of bridges, and equations of binding were derived. The results of calculations were compared with the experimental data. Within the framework of each variant, the values of the energy of interaction between the daunomycin molecule and the copper ion in the bridge, the energy of interaction of the daunomycin molecule with the nucleic acid, and the length of the bridge were varied. For all variants, those values of the parameters were chosen that fit best the experimental data. The theoretical curves obtained using the three variants of the model agree rather well with the family of experimental curves. The best agreement between the theoretical and experimental data was obtained when the polymeric chelate bridge includes more than two daunomycin molecules.
研究了固定在液晶分散体颗粒结构中的核酸分子之间形成“桥”的三种模型变体。这三种变体的共同之处在于，桥是由柔红霉素和铜离子交替分子组成的聚合物螯合交联。三种变体的不同之处在于，在第一种变体中，桥以柔红霉素分子开始和结束，这些柔红霉素分子通过与核酸的外部结合机制形成复合物；在第二种变体中，桥以与核酸碱基对结合的铜离子开始和结束；在第三种变体中，桥以柔红霉素分子开始，以铜离子结束。对于每种变体，构建了描述桥形成的数学模型，并推导了结合方程。将计算结果与实验数据进行了比较。在每种变体的框架内，改变桥中柔红霉素分子与铜离子之间的相互作用能、柔红霉素分子与核酸的相互作用能以及桥的长度值。对于所有变体，选择最符合实验数据的参数值。使用该模型的三种变体获得的理论曲线与实验曲线族相当吻合。当聚合物螯合桥包含两个以上的柔红霉素分子时，理论数据与实验数据之间的一致性最佳。
