Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China.
Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China.
Int J Biol Macromol. 2021 Jan 15;167:854-861. doi: 10.1016/j.ijbiomac.2020.11.042. Epub 2020 Nov 10.
Polycyclic aromatic hydrocarbons are environmental pollutants with strong carcinogenicity, indirect teratogenicity, and mutagenicity. This study explored the interaction mechanism of benzo(a)pyrene with free DNA in vitro by using various analytical methods. UV-vis spectra showed that benzo(a)pyrene and DNA formed a new benzo(a)pyrene-DNA complex. The thermal melting temperature of DNA increased by 12.7 °C, showing that the intercalation of benzo(a)pyrene into DNA could promote the stability of the DNA double helix structure. The intercalation of benzo(a)pyrene with DNA in vitro was further confirmed by fluorescence microscopy with magnetic beads. Fluorescence spectra showed that the interaction between DNA and benzo(a)pyrene decreased the fluorescence intensity of benzo(a)pyrene, and the maximum quenching rate was 27.89%. The quenching mode of benzo(a)pyrene was static quenching. Thermodynamic data showed that the main driving forces were van der Waals forces and hydrogen bonds, and the reaction was spontaneous. The results of this study provided a novel insight for the establishment of polycyclic aromatic hydrocarbon capture and elimination through polycyclic aromatic hydrocarbon-DNA intercalation.
多环芳烃是具有强致癌性、间接致畸性和致突变性的环境污染物。本研究采用多种分析方法探讨了苯并(a)芘与游离 DNA 在体外的相互作用机制。紫外可见光谱表明，苯并(a)芘与 DNA 形成了一种新的苯并(a)芘-DNA 复合物。DNA 的热融解温度升高了 12.7°C，表明苯并(a)芘的嵌入可以促进 DNA 双螺旋结构的稳定性。用带有磁珠的荧光显微镜进一步证实了苯并(a)芘与 DNA 的体外插入。荧光光谱表明，DNA 与苯并(a)芘的相互作用降低了苯并(a)芘的荧光强度，最大猝灭率为 27.89%。苯并(a)芘的猝灭方式为静态猝灭。热力学数据表明，主要驱动力是范德华力和氢键，反应是自发的。本研究的结果为通过多环芳烃-DNA 嵌入建立多环芳烃捕获和消除提供了新的见解。
