Young P R, Kallenbach N R
Proc Natl Acad Sci U S A. 1980 Nov;77(11):6453-7. doi: 10.1073/pnas.77.11.6453.
The interaction of the mutagenic dye 9-aminoacridine (9AA) with the self-complementary tetranucleotide dpApGpCpT has been studied by a combination of proton NMR titrations and thermal denaturation experiments. A minimum of three complexes of well-defined stoichiometry can be demonstrated in this system. Complex I is a 1:2 9AA/tetranucleotide structure occurring in the presence of excess tetranucleotide. The dye appears to intercalate within the GpC/GpC site of a tetranucleotide duplex. Complex II is a 2:2 9AA/tetranucleotide structure, with two dyes intercalated at the ApG/CpT sites of the duplex. Complex III is a low-temperature 4:2 9AA/tetranucleotide structure containing two dye molecules stacked over the terminal A-T residues of the duplex in addition to those present in complex II. These results show that both sequence selectivity and site exclusion can occur in this model system.
通过质子核磁共振滴定和热变性实验相结合的方法，研究了诱变染料9-氨基吖啶（9AA）与自互补四核苷酸dpApGpCpT的相互作用。在该体系中至少可以证明存在三种化学计量明确的复合物。复合物I是在过量四核苷酸存在下形成的1:2 9AA/四核苷酸结构。染料似乎插入到四核苷酸双链体的GpC/GpC位点内。复合物II是2:2 9AA/四核苷酸结构，有两个染料插入到双链体的ApG/CpT位点。复合物III是一种低温下的4:2 9AA/四核苷酸结构，除了复合物II中存在的染料分子外，还包含两个堆叠在双链体末端A-T残基上的染料分子。这些结果表明，在这个模型系统中既可以发生序列选择性，也可以发生位点排斥。
