氟虫腈与昆虫γ-氨基丁酸受体相互作用研究
Interactions between the fipronil and the insect γ-aminobutyric acid receptor

利用荧光标记法及分子模拟法,研究了氟虫腈与昆虫γ-氨基丁酸(aminobutyric acid,GABA)受体的相互作用。荧光标记试验结果显示,氟虫腈与家蝇脑内GABA受体有较强的相互作用,其最大结合量[RT]值和亲和常数Kd值分别为(21.3±2.5) pmol/mg protein和(109±9) nmol/L。分子模拟结果显示:氟虫腈与果蝇RDL受体间形成3条氢键;两者之间的CDOCKER的相互作用能为-137.93 kJ/mol。试验和理论两方面均证实,氟虫腈对昆虫GABA受体的强亲和性是导致氟虫腈对昆虫产生高毒性的重要原因。
Herein the fluorescent-labeled ligand and the molecular simulation method were used to study the interactions between the γ-aminobutyric acid (GABA) receptor of the insects and fipronil. The fluorescence labeling experiment results showed that strong interactions were existed between fipronil and the GABA receptor in the brain of the housefly. The maximum number of binding site[RT] and the equilibrium dissociation constants (Kd) were (21.3±2.5) pmol/mg protein and (109±9) nmol/L, respectively. Furthermore, the molecular simulation results also suggested that there were some strong hydrogen bond interactions between fipronil and the RDL receptor of the fruit fly. In addition, the CDOCKER interaction energy between them was-137.93 kJ/mol. The above results clearly illustrated that the fipronil has strong affinity on the GABA receptor of insects and high toxicity to insects.