The interaction of herring sperm DNA with the 1,4,5,8-naphthalene diimide–spermine conjugate (NDIS) was studied by UV/vis absorption, fluorescence and CD spectroscopic methods. Compared with the 1,8-naphthalimide–spermidine conjugate (NIS), the values of K_SV (quenching constant) and K_b (binding constant) of NDIS were larger, and the hypochromic effect in the UV/vis spectra and the quenching effect in the fluorescence of NDIS were more significant. The interaction mode between NDIS and DNA was mainly groove binding. The fluorescence experiments at varying temperatures showed that the binding process of NDIS and DNA was static, as both hydrogen bonds and hydrophobic forces played a major role in the binding of NDIS and DNA. The CD spectrum indicated that NDIS caused a conformational change, like the B to A-DNA transition, and the tests using KI and NaCl and ¹H NMR spectroscopy indicated that NDIS was not a classical DNA inserter. All the results demonstrated that both the polyamine side chain and the aromatic rings affect the process of NDIS binding to DNA, which is thus obviously different from that of NIS. The conclusion was confirmed by the in silico molecular docking experiments.

中文翻译：

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用光谱法和分子对接研究1,4,5,8-萘二酰亚胺-亚精胺共轭物（NDIS）与DNA的相互作用

通过紫外/可见吸收，荧光和CD光谱法研究了鲱鱼精子DNA与1,4,5,8-萘二酰亚胺-精胺结合物（NDIS）的相互作用。与1,8-萘二甲酰亚胺-亚精胺共轭物（NIS）相比，K _SV（淬灭常数）和K _b的值NDIS的（结合常数）更大，并且在UV / vis光谱中的减色作用和在NDIS的荧光中的猝灭作用更显着。NDIS与DNA之间的相互作用模式主要是凹槽结合。在不同温度下的荧光实验表明，NDIS和DNA的结合过程是静态的，因为氢键和疏水力在NDIS和DNA的结合中起主要作用。CD光谱表明NDIS引起构象变化，例如从B到A-DNA的转变，以及使用KI和NaCl和¹的测试1 H NMR光谱表明NDIS不是经典的DNA插入物。所有结果表明，多胺侧链和芳环均影响NDIS与DNA的结合过程，因此与NIS明显不同。通过计算机分子对接实验证实了该结论。