Linear and circular dichroism studies of DNA-monoaminoacridine complexes
Linear and circular dichroism studies of DNA-monoaminoacridine complexes
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DNA-单氨基吖啶复合物的线性和圆二色性研究
DOI：
10.1039/tf9716700966
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发表时间：
1971
影响因子：
--
通讯作者：
S. Mason
中科院分区：
文献类型：
--
作者：
K. Jackson;S. Mason
DNA 与 1-、2-、3-、4- 和 9- 氨基吖啶以及四种单氨基苯扎吖啶复合物的圆二色光谱已在一定范围的 DNA-磷酸盐与染料比率下测量，对于 9-氨基苯并[a]吖啶复合物，在 pH 范围 3.3-10 以及高和低离子强度下测量。 DNA-染料复合物的流动溶液的线性二色光谱是通过平行和垂直于流动方向传播的光获得的。已通过分光光度法和极谱法测定了结合染料的分数和游离染料浓度之间的关系。发现在生理pH下的结合程度与单氨基吖啶的相对抗菌和诱变活性相关。光谱结果支持 DNA-吖啶复合物的修改嵌入模型，其中结合的吖啶分子夹在连接到共同糖磷酸链的两个相邻碱基之间，并且它们表明，除了由于结合染料的嵌入之外，pH 的降低还会导致 DNA 螺旋的两条链解旋。
The circular dichroism spectra of the DNA complexes with 1-, 2-, 3-, 4- and 9-aminoacridine and with four monoaminobenzacridines have been measured over a range of DNA-phosphate to dye ratios and, in the case of the 9-aminobenzo[a]acridine complex, over the pH range 3.3–10 and at high and low ionic strength. The linear dichroism spectra of streaming solutions of the DNA-dye complexes have been obtained with light propagated parallel and perpendicular to the flow-direction. The relations between the fraction of dye bound and the free dye concentration have been determined by spectrophotometric and by polarographic methods. The degree of binding at physiological pH is found to correlate with the relative antibacterial and mutagenic activities of the monoaminoacridines. The spectroscopic results support a modified intercalation model for the DNA-acridine complex in which the bound acridine molecule is sandwiched between two adjacent bases attached to a common sugar phosphate chain, and they indicate that a reduction of pH produces an unwinding of the two strands of the DNA helix additional to that due to the intercalation of bound dye.