期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1980
卷号：77
期号：11
页码：6453-6457
DOI：10.1073/pnas.77.11.6453
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：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.
