Salyanov V I, Dembo A T, Berg H
Biomed Biochim Acta. 1983;42(7-8):855-66.
In the presence of polyethyleneglycol water-salt solutions, DNA is condensed to a kind of mesophase (liquid crystals). The peculiar properties of this phase caused by anisotropic orientations have been analyzed by circular dichroism (CD) of condensed particles of DNA complexed with dyes, i.e. anthracycline antibiotics (daunomycin, aclacinomycin A), actinomycin, and ethidium bromide. The anthracycline complexes show intense CD bands in the visible and the UV region. Daunomycin induces a typical reversal of the sign of these CD bands with increasing occupation of the double helix contrary to the other ligands. This characteristic effect and its partial reversal after removal of daunomycin from the condensed particles can be the result of the change of the direction of the mesophase helical twist owing to an energy change of interaction between DNA molecules, and partially to a modification of base-plane inclination (tilt), too. This new type of DNA complex state is characterized in detail.
在聚乙二醇水盐溶液存在的情况下，DNA会凝聚成一种中间相（液晶）。通过与染料（即蒽环类抗生素（柔红霉素、阿克拉霉素A）、放线菌素和溴化乙锭）复合的DNA凝聚颗粒的圆二色性（CD）分析了由各向异性取向引起的该相的特殊性质。蒽环类复合物在可见光和紫外区域显示出强烈的CD带。与其他配体相反，随着双螺旋占据率的增加，柔红霉素会导致这些CD带的符号发生典型反转。这种特征效应以及从凝聚颗粒中去除柔红霉素后其部分反转可能是由于DNA分子间相互作用能量变化导致中间相螺旋扭曲方向改变的结果，部分也是由于碱基平面倾斜度（倾斜）的改变。详细表征了这种新型的DNA复合状态。
