Borovik A S, Kalambet Y A, Lyubchenko Y L, Shitov V T, Golovanov E I
Nucleic Acids Res. 1980 Sep 25;8(18):4165-84. doi: 10.1093/nar/8.18.4165.
The fine structure of the melting curve for the linear colE1 DNA has been obtained. To find the ColE1 DNA regions corresponding to peaks in the melting curve's fine structure, we fixed the melted DNA regions with glyoxal /12/. Electron-microscopic denaturation maps were obtained for nine temperature points within the melting range. Thereby the whole process of colE1 DNA melting was reconstructed in detail. Spectrophotometric and electron microscopic data were used for mapping the distribution of Gc-pairs over the DNA molecule. The most AT-rich DNA regions (28 and 37% of GC-pairs), 380 and 660 bp long resp., are located on both sides of the site of ColE1 DNA's cleavage by EcoR1 endonuclease. The equilibrium denaturation maps are compared with maps obtained by the method of Inman /20/ for eight points of the kinetic curve of ColE1 DNA unwinding by formaldehyde.
已获得线性大肠杆菌素E1 DNA熔解曲线的精细结构。为了找到与熔解曲线精细结构中的峰相对应的大肠杆菌素E1 DNA区域，我们用乙二醛固定了熔解的DNA区域/12/。在熔解范围内的九个温度点获得了电子显微镜变性图谱。从而详细重建了大肠杆菌素E1 DNA的整个熔解过程。分光光度法和电子显微镜数据用于绘制DNA分子上鸟嘌呤-胞嘧啶碱基对（Gc对）的分布。富含腺嘌呤-胸腺嘧啶（AT）的DNA区域最长分别为380和660碱基对（占Gc对的28%和37%），位于大肠杆菌素E1 DNA被EcoR1核酸内切酶切割位点的两侧。将平衡变性图谱与通过英曼方法/20/获得的关于甲醛使大肠杆菌素E1 DNA解链动力学曲线八个点的图谱进行了比较。
