基于高分辨质谱及分子对接技术研究适配体与倍氯米松的相互作用  

The Interaction between Aptamer and Beclomethasone Based on High Resolution Mass Spectrometry and Molecular Docking

作　　者：樊洪利 刘亚雄[2] 李苏亚 曾文杰 罗卓雅[2] FAN Hong-Li;LIU Ya-Xiong;LI Su-Ya;ZENG Wen-Jie;LUO Zhuo-Ya(College of Traditinal Chinese Medicine,Guangzhou University of Chinese Medicine,Guangzhou 510006,China;NMPA Key Laboratory for Rapid Testing Technology of Drugs,Guangdong Institute for Drugs Control,Guangzhou 510663,China;C ollege of Pharmacy,Guangzhou Medical University,Guangzhou 511436,China)

机构地区：[1]广州中医药大学中药学院,广州510006 [2]广东省药品检验所,国家药品监督管理局药品快速检验技术重点实验室,广州510663 [3]广州医科大学药学院,广州511436

出　　处：《中国生物化学与分子生物学报》2021年第5期636-643,共8页Chinese Journal of Biochemistry and Molecular Biology

基　　金：广东省生物医药科技协同创新中心(No.ZA20190010)资助。

摘　　要：倍氯米松(beclomethasone)是一种有效的糖皮质激素,而倍氯米松适配体是对倍氯米松具有亲和力与特异性的单链DNA分子。目前对两者的相互作用仍不清楚,研究适配体与药物的相互作用对适配体的应用具有一定的意义。本研究采用高分辨傅里叶变换离子回旋共振质谱仪(FT-MS)及分子对接软件计算模拟研究适配体与倍氯米松的相互作用。首先,在优化的高分辨质谱条件下,通过电喷雾离子源负离子扫描模式对适配体与倍氯米松复合物进行检测。测得复合物多为-8价离子。在饱和前,适配体与倍氯米松化学结合计量数之比为1∶1,其解离常数Kd值为1.01±0.23μmol/L。经分子对接软件模拟,获得适配体与倍氯米松的化学结合计量数之比为1∶1,两者结合自由能为-24 kcal/mol,主要以氢键作用力相结合。最后,使用超微量紫外检测两者结合前后的吸收波长变化以验证两者的结合,并获得适配体与倍氯米松复合物的解离常数Kd值为1.67±0.35μmol/L,其结果与高分辨FT-MS结果相近。高分辨FT-MS检测与分子对接模拟不仅提供了适配体与倍氯米松的亲和力,也提供了两者的化学结合计量数之比等其它相互作用信息,对深化适配体的应用具有一定的意义。Beclomethasone is an effective glucocorticoid, and beclomethasone-aptamer is a short single-stranded DNA with affinity and specificity to beclomethasone. The interaction between them is still unclear. The study of the interaction between aptamers and beclomethasone has a certain significance for the application of aptamers. In this study, high-resolution Fourier transform ion cyclotron resonance mass spectrometer(FT-MS) and molecular docking simulation technology were used to study the interaction between aptamer and beclomethasone. Firstly, under the optimized conditions of high-resolution mass spectrometry parameters, the complex of aptamer and beclomethasone was detected by the negative ion scanning mode with the electrospray ion source. Based on the results of high-resolution mass spectrometry, most of the compounds were-8-valent ions, and their dissociation constant Kd value was 1.01 ± 0.23 μmol/L, as well as the stoichiometric number of the two was 1∶1 before saturation. Secondly, molecular docking simulation showed that the stoichiometric number of binding between aptamer and beclomethasone was also 1∶1, and the free energy of binding between them was-24 kcal/mol, and they were combined by hydrogen bond force. Finally, Ultra-micro UV was also used to detect the binding between aptamer and beclomethasone through the changes of absorption wavelength before and after the combination. The dissociation constant Kd of the beclomethasone-aptamer complex is 1.67 ± 0.35 μmol/L, which is similar to that of high resolution FT-MS. The detection of FT-MS and molecular docking simulation not only provide the affinity of the aptamer and beclomethasone, but also provide other interaction information such as the ratio of chemical binding stoichiometry between them, which has a certain significance for deepening the application of aptamers.

关 键 词：高分辨傅里叶变换离子回旋共振质谱仪 分子对接 适配体 倍氯米松 

分 类 号：Q31[生物学—遗传学]