Glutathione S-transferase in the defence against pyrethroids in insects
Glutathione S-transferase in the defence against pyrethroids in insects
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DOI：
10.1016/s0965-1748(00)00123-5
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发表时间：
2001-03-15
影响因子：
3.8
通讯作者：
Papadopoulou-Mourkidou, E
中科院分区：
文献类型：
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作者：
Kostaropoulos, I;Papadopoulos, AI;Papadopoulou-Mourkidou, E
研究了 GST 天然水平与杀虫剂十甲菊酯 (dMT) 耐受性之间的相关性，以及亲和纯化酶分子与杀虫剂之间的相互作用，以收集有关谷胱甘肽 S-转移酶系统 (GST) 作为拟除虫菊酯防御机制的模糊作用的进一步信息。相比之下，这些研究是在鞘翅目黄粉虫的幼虫和蛹发育阶段进行的，这些阶段表现出不同的自然 GST 活性水平。在最初的24小时内，没有发现昆虫对拟除虫菊酯杀虫剂的阶段依赖性敏感性，但是在处理后48小时，由于一些个体从幼虫阶段恢复，KD50剂量显着增加。同时注射十氢菊酯和体外抑制 GST 活性的化合物，导致耐受性增加，这在蛹阶段更为明显。结合竞争性荧光光谱和高压液相色谱 (HPLC) 的抑制研究表明，该杀虫剂可能与酶的活性位点结合，以竞争性方式抑制其对 CDNB 的活性，但不与 GSH 结合。据此，GST 通过以隔离机制与拟除虫菊酯杀虫剂分子结合，提供对拟除虫菊酯杀虫剂的被动保护。 (C) 2001 Elsevier Science Ltd. 保留所有权利。
The correlation between the natural levels of GST and the tolerance to the insecticide decamethrin (dMT), as well as the interaction between the molecules of affinity purified enzyme and the insecticide were investigated in order to collect further information on the obscure role of the Glutathione S-transferase system (GST) as a mechanism of defence against pyrethroids. The studies were carried out, comparatively, on the larvae and pupae developmental stages of the coleopteran Tenebrio molitor, which exhibit varying natural levels of GST activity. No stage dependent susceptibility of the insect against pyrethroid insecticides was found during the first 24 h, however 48 h after treatment, the KD50 dose increased significantly due to the recovery of some individuals from the larvae stage. Simultaneous injection of decamethrin with compounds which inhibit GST activity in vitro, resulted in an increased tolerance, which was more pronounced in the pupae stage. Inhibition studies combined with competitive fluorescence spectroscopy and high pressure liquid chromatography (HPLC) showed that the insecticide binds probably to the active site of the enzyme inhibiting its activity towards CDNB in a competitive manner, but is not conjugated with GSH. According to this, GST offers a passive protection towards pyrethroid insecticides by binding to their molecule in a sequestering mechanism. (C) 2001 Elsevier Science Ltd. All rights reserved.