Gentz Margaret C, Jones Alun, Clement Herlinda, King Glenn F
Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Road, St. Lucia, QLD 4072, Australia.
Toxicon. 2009 Apr;53(5):496-502. doi: 10.1016/j.toxicon.2009.01.025.
We screened a panel of theraphosid venoms in two orders of insect in order to determine whether these bioassays would help in the selection of candidate venoms for future discovery of insecticidal toxins. Venoms from six different theraphosid genera were compared with venom from the Australian funnel-web spider Hadronyche infensa (Hexathelidae). The tarantulas included were Coremiocnemis tropix, Selenocosmia crossipes, and Selenotholus foelschei from Australia and Brachypelma albiceps and Brachypelma hamorii from Mexico. The insects assayed, Tenebrio molitor (Coleoptera: Tenebrionidae) and Acheta domesticus (Orthoptera: Gryllidae), were selected because of their relevance as model holometabolous and hemimetabolous insects, respectively, as well as their taxonomic relationship to economically important pest insects. Despite significant differences in their peptide/protein profiles as determined using SDS-PAGE, HPLC, and mass spectrometry, all of the theraphosid venoms exhibited remarkably similar LD50 values of 46-126 microg/g for crickets and 0.5-4.0 microg/g for mealworms. Notably, mealworms were on average 50-fold more susceptible than crickets to each of the crude theraphosid venoms and consequently they provide an excellent bioassay system when venom supply is limited. This study indicates that even closely related spiders have evolved quite different toxin repertoires that nevertheless have comparable efficiency with respect to killing their primary prey, namely insects.
我们在两类昆虫中筛选了一组捕鸟蛛毒液，以确定这些生物测定法是否有助于为未来发现杀虫毒素选择候选毒液。将六种不同捕鸟蛛属的毒液与澳大利亚漏斗网蜘蛛哈氏蛛（六疣蛛科）的毒液进行了比较。所包括的狼蛛有来自澳大利亚的热带核螯蛛、红螯蛛和费氏螯蛛，以及来自墨西哥的墨西哥金背蛛和墨西哥铁锈尾蛛。所测定的昆虫，分别是黄粉虫（鞘翅目：拟步甲科）和家蟋蟀（直翅目：蟋蟀科），选择它们是因为它们分别作为全变态和渐变态昆虫模型具有相关性，以及它们与经济上重要的害虫昆虫的分类关系。尽管使用SDS - PAGE、HPLC和质谱法测定的肽/蛋白质谱存在显著差异，但所有捕鸟蛛毒液对蟋蟀的LD50值都非常相似，为46 - 126微克/克，对黄粉虫的LD50值为0.5 - 4.0微克/克。值得注意的是，黄粉虫对每种粗制捕鸟蛛毒液的敏感性平均比蟋蟀高50倍，因此当毒液供应有限时，它们提供了一个极好的生物测定系统。这项研究表明，即使是亲缘关系密切的蜘蛛也进化出了截然不同的毒素库，但在杀死它们的主要猎物即昆虫方面却具有相当的效率。
