塑化剂邻苯二甲酸二丁酯与小牛胸腺DNA的沟槽结合  

Groove Binding of Phthalic Acid Esters Plasticizer(Dibutyl Phthalate)with Calf Thymus DNA

作　　者：李松[1] 张国文[1] 

机构地区：[1]南昌大学食品科学与技术国家重点实验室,江西南昌330047

出　　处：《分析科学学报》2016年第5期593-599,共7页Journal of Analytical Science

基　　金：国家自然科学基金(No.21167013,31460422);高等学校博士点基金(No.20123601110005);江西省自然科学基金(No.20143ACB20006,20142BAB204001);江西省科技支撑项目(No.20141BBG70092);食品科学与技术国家重点实验室基金(No.SKLF-ZZB-201305,SKLF-ZZA-201612)

摘　　要：运用多种光谱学方法,结合化学计量学多元曲线分辨-交替最小二乘法(MCRALS),以及分子模拟技术,在人体生理酸度(pH=7.4)条件下研究了邻苯二甲酸二丁酯(DBP)与小牛胸腺DNA(ctDNA)的相互作用。采用MCR-ALS法分析了DBP与ctDNA作用的紫外光谱数据矩阵,结果表明DBP与ctDNA作用形成了DBP-ctDNA复合物。荧光猝灭实验显示,ctDNA对DBP的荧光猝灭属于形成复合物的单一静态猝灭,其主要驱动力为疏水作用和氢键。通过单双链、熔点和粘度等实验证明DBP与ctDNA发生了沟槽结合,结合区域为A、T碱基富集区。圆二色谱和琼脂糖凝胶电泳分析表明,DBP与ctDNA结合导致ctDNA结构变得更为松散,但未造成质粒DNA损伤。分子模拟形象直观地展现了两者的结合姿态,预测结果与实验结果吻合。The binding interaction of dibutyl phthalate（DBP）with calf thymus DNA（ctDNA）was investigated in a simulated physiological condition（pH=7.4）by multifaceted spectral methods combined with chemometrics multivariate curve resolution-alternating least squares（MCR-ALS）and molecular simulation technique.The data matrix obtained from UV-vis spectra was resolved by MCR-ALS approach which indicated that DBP-ctDNA complex was formed.Fluorescence data revealed that fluorescence quenching of DBP by ctDNA was a static process,and the main driving forces were hydrophobic interaction and hydrogen bonds.The groove binding mode between DBP and ctDNA was proved by melting studies,viscosity measurements and comparison interactions of native and denatured ctDNA with DBP.Analysis of the Fourier transform infrared spectra showed that DBP preferentially bound to A-T rich region of ctDNA.The circular dichroism signals indicated the conformation of ctDNA turned into a more highly wound form of B-conformation.Meanwhile,results of gel electrophoresis suggested that DBP did not induce obvious damage on plasmid DNA.Moreover,molecular docking exhibited the binding posture of DBP with DNA in a visualized way,and the predicted results were consistent with the experimental results.

关 键 词：邻苯二甲酸二丁酯 小牛胸腺DNA 沟槽结合 化学计量学 分子模拟 

分 类 号：O657.3[理学—分析化学]