Specificity of Activated CryIA Proteins from Bacillus thuringiensis subsp. kurstaki HD-1 for Defoliating Forest Lepidoptera
Specificity of Activated CryIA Proteins from Bacillus thuringiensis subsp. kurstaki HD-1 for Defoliating Forest Lepidoptera
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苏云金芽孢杆菌亚种活化 CryIA 蛋白的特异性。
DOI：
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发表时间：
1991
影响因子：
4.4
通讯作者：
L. Masson
中科院分区：
文献类型：
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作者：
K. Frankenhuyzen;J. Gringorten;R. Milne;D. Gauthier;M. Pusztai;R. Brousseau;L. Masson
对来自苏云金芽孢杆菌亚种的CryIA（a）、CryIA（B）和CryIA（c）毒素的杀虫活性进行了研究。kurstakiHD-1对烟卷蛾Choristoneurafumiferana、烟卷蛾C. occurentalis、C.松属、舞毒蛾（Lymantria dispar）、白点舞毒蛾（Orgyia leucostigma）、分布天幕毛虫（Malacosoma disstria）和芬兰Actebia fennica。毒素是从大肠杆菌中表达的克隆原毒素基因获得的。用家蚕幼虫的肠液激活原毒素。个体基因产物以及天然HD-1毒素的生物活性被评估为在3天内防止50%的昆虫产生粪便的剂量（粪便失效剂量[FFD 50]）。三种毒素对M. disstria。在Choristoneura物种中，CryIA（a）和CryIA（B）的毒性比CryIA（c）高出5倍。在毒蛾种类中，CryIA（a）和CryIA（B）的毒性比CryIA（c）高100倍。在所有这些种属中，HD-1的毒性与单个CryIA（a）或CryIA（B）毒素的毒性相似。CryIA毒素和HD-1对A.芬尼卡。观察到的FFD50的HD-1与FFD50的基础上，其晶体组成的预期的比较表明，在两个毒蛾物种的毒素可能的协同效应。我们的研究结果进一步说明了这些高度相关的蛋白质的活性谱的多样性，并提供了一个数据基础，以森林昆虫的研究，以阐明毒素特异性的分子基础。
The insecticidal activity of the CryIA(a), CryIA(b), and CryIA(c) toxins from Bacillus thuringiensis subsp. kurstaki HD-1 was determined in force-feeding experiments with larvae of Choristoneura fumiferana, C. occidentalis, C. pinus, Lymantria dispar, Orgyia leucostigma, Malacosoma disstria, and Actebia fennica. The toxins were obtained from cloned protoxin genes expressed in Escherichia coli. The protoxins were activated with gut juice from Bombyx mori larvae. Biological activity of the individual gene products as well as the native HD-1 toxin was assessed as the dose which prevented 50% of the insects from producing frass within 3 days (frass failure dose [FFD50]). The three toxins were about equally active against M. disstria. In the Choristoneura species, CryIA(a) and CryIA(b) were up to fivefold more toxic than CryIA(c). In the lymantriid species, CryIA(a) and CryIA(b) were up to 100-fold more toxic than CryIA(c). The toxicity of HD-1 was similar to that of the individual CryIA(a) or CryIA(b) toxins in all of these species. None of the CryIA toxins or HD-1 exhibited and toxicity towards A. fennica. Comparison of the observed FFD50 of HD-1 with the FFD50 expected on the basis of its crystal composition suggested a possible synergistic effect of the toxins in the two lymantriid species. Our results further illustrate the diversity of activity spectra of these highly related proteins and provide a data base for studies with forest insects to elucidate the molecular basis of toxin specificity.