新型靶向αvβ6多肽的设计、合成与亲和力评价  

Design,Synthesis and Affinity Evaluation of Novel Targetedαvβ6 Polypeptides

作　　者：李跃鹏 王远强 LI Yuepeng;WANG Yuanqiang(School of Pharmacy and Bioengineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学药学与生物工程学院,重庆400054

出　　处：《吉林大学学报（理学版）》2024年第1期181-188,共8页Journal of Jilin University:Science Edition

基　　金：重庆市科学技术局自然科学基金(批准号:CSTB2022NSCQ-MSX1327);重庆市人力资源和社会保障局留学人员回国创业创新支持计划项目(批准号:cx2020012)。

摘　　要：通过计算机辅助药物设计策略及固相合成法设计并筛选具有全新结构的αvβ6多肽配体,并用酶联免疫吸附法(ELISA)测定多肽配体与αvβ6的结合亲和力,建立αvβ6多肽配体的筛选方案.首先用Sybyl-X 1.3对αvβ6多肽配体及天然配体进行分子对接;其次用Amber 16对分子对接结果进行分子动力学模拟,确定多肽配体与αvβ6蛋白之间的结合模式,并以RGDLXXL(X为任意氨基酸)为多肽配体核心结构,通过逐步延伸氨基酸构建虚拟肽库,筛选获得长度为7~10个氨基酸的多肽配体,进一步通过相似氨基酸替换的方法设计筛选不同于RGDLXXL核心的新的多肽配体;最后用固相合成法合成新设计的多肽配体,利用间接ELISA法测定多肽配体-αvβ6的结合亲和力.已有多肽配体和天然配体的分子对接以及分子动力学模拟结果表明,αvβ6与配体的结合主要通过Asp218和多肽配体之间形成氢键,以及Mg2+和多肽配体形成金属螯合作用完成.结合虚拟组合筛选与相似氨基酸替换,发现GRTDLGTLLFR,GRRTDLATIHG,RTDVGRVRGRG和RGDVGRVGR等多肽均满足该结合模式,RTDVGRVRGRG与αvβ6的亲和力为10.76μmol/L.可见RTDVGRVRGRG与αvβ6亲和力良好,是一条全新的αvβ6多肽配体.We designed and screenedαvβ6 polypeptide ligands with new structure by using computer-aided drug design strategy and solid--phase synthesis method,and determined the binding affinity between the polypeptide ligands andαvβ6 by using enzyme--linked immunosorbent assay(ELISA)to establish a screening scheme forαvβ6 polypeptide ligands.Firstly,Sybyl--X 1.3 was used to perform molecular docking of theαvβ6 polypeptide ligands and natural ligands.Secondly,Amber 16 was used to perform molecular dynamics simulation to determine the binding mode between the polypeptide ligands andαvβ6 protein,and RGDLXXL(X was any amino acid)was used as the core structure of the polypeptide ligand,the virtual peptide library was constructed by gradual extension of amino acids,polypeptide ligands with a length of 7—10 amino acids were screened,and new polypeptide ligands different from the core of RGDLXXL were designed and screened by similar amino acid substitution method.Finally,the newly designed polypeptide ligands were synthesized by solid--phase synthesis method,and the binding affinity of polypeptide ligand-αvβ6 was determined by indirect ELISA method.The molecular docking and molecular dynamics simulation results of polypeptide ligands and natural ligands show that the binding ofαvβ6 to the ligand is mainly achieved through the hydrogen bond formation between Asp218 and the polypeptide ligand,and the metal chelation between Mg 2+and the polypeptide ligand.Combined with virtual combination screening and similar amino acid substitution,we find that polypeptides such as GRTDLGTLLFR,GRRTDLATIHG,RTDVGRVRGRG and RGDVGRVGR all meet this binding pattern,and the affinity between RTDVGRVRGRG andαvβ6 is 10.76μmol/L.Therefore,RTDVGRVRGRG andαvβ6 have a good affinity and are a newαvβ6 polypeptide ligand.

关 键 词：整合素ΑVΒ6 多肽配体 药物设计 亲和力 酶联免疫吸附法 

分 类 号：R914.2[医药卫生—药物化学]