小菜蛾性信息素与性信息素结合蛋白、受体蛋白结合机理研究

【目的】研究小菜蛾性信息素与性信息素结合蛋白、受体蛋白之间作用的关键氨基酸残基和作用力类型,揭示小菜蛾识别性信息素的分子机制,为开发新型性诱剂和小菜蛾的无害化防治提供新思路。【方法】运用Discovery Studio 2.5对小菜蛾性信息素结合蛋白PxylPBP2和受体蛋白PxylOR4进行同源建模,运用程序包中LibDock模块进行分子对接,运用Calculate Energy模块计算复合物结合自由能,分析性信息素Z9-14∶AC与PxylPBP2和PxylOR4的结合模式及相互作用力。【结果】Thr9是PxylPBP2与Z9-14∶AC形成氢键的关键氨基酸残基,Z9-14∶AC易与PxylOR4中的Leu残基产生疏水作用力;PxylPBP2与Z9-14∶AC结合的主要驱动力是静电力,PxylOR4与Z9-14∶AC结合的主要驱动力是范德华力,溶剂化能均抑制Z9-14∶AC与PxylPBP2和Z9-14∶AC与PxylOR4的结合。【结论】小菜蛾性信息素受体蛋白和性信息素结合蛋白在识别和结合性信息素分子方面存在明显差异,性信息素受体蛋白与性信息素反应更灵敏、形成的复合物更稳定。

Binding mechanisms of sex pheromone with pheromone binding and receptor proteins in Plutella xylostella

Objective]The present experiment was conducted to reveal molecular mechanism of recognition of sex pheromone by studying key amino acid residues and interaction force types among sex pheromone binding protein , recep-tor protein and sex pheromone of Plutella xylostella, in order to provide new ideas for development of new sex lures and harmless control of Plutella xylostella. Method]The binding mode and interactions between Z9-14∶AC and any of PxylPBP2 and PxylOR4 were analyzed through the molecular docking with LibDock module and the free energy calculation with Cal-culate Energy module of Discovery Studio 2.5 software. Result]Thr9 was responsible for the formation of hydrogen bond between Z9-14∶AC and PxylPBP2. Besides, Z9-14∶AC tended to produce hydrophobic interaction with Leu residues. The main driving force of the docking between Z9-14∶AC and PxylPBP2 was electrostatic energy, while the main driving force of the docking between Z9-14∶AC and PxylOR4 was van der Waals energy, but the binding of Z9-14∶AC and PxylPBP2 as well as Z9-14∶AC and PxylOR4 were suppressed by solvation energy. Conclusion]There are significant differences in the recognition and combination of sex pheromone molecules between the sex pheromone receptor protein , and sex pheromone binding protein in diamondback moth, as the former protein responds to sex pheromone more sensitively, and the compound is more stable.