摘要
以新筛选的对鞘翅目、鳞翅目、双翅目均具毒性的Ｂ．ｔ．Ｔｍ１３－１４菌株为材料，用ＨＤ－１、３３７０－１为参考菌株，比较了伴孢晶体蛋白的多肽组成，以及经三种昆虫肠道酶降解产生的抗酶多肽组分。ＳＤＳ－ＰＡＧＥ分析表明：Ｔｍ１３－１４晶体蛋白含１３８ｋＤ、１３２ｋＤ主要成分和６５ｋＤ次要成分。其晶体分别由三种昆虫肠道酶消化产生绚毒性多肽，经生物测定，杀家蚕的毒性成分为６８．５ｋＤ、５９ｋＤ多肽；杀斜纹夜蛾毒性成分为７１ｋＤ，６７ｋＤ和５９．６ｋＤ多肽杀马铃薯瓢虫毒性成分为６９ｋＤ、６５ｋＤ多肽。它与ＨＤ－１、３３７０－１晶体均有明显差异。
The protein components of the delta-endotoxin crystals from Bacillusthuringiensis HD--1 (toxic to Lepidoptera), 3370--1 (nontoxic) and Tm13--14 (toxicto Lepidoptera, Diptera, and Coleoptera) were compared under the different lysatedcondition by SDS--PAGE. The results showed that Tm13--14 crystal contains twomajor peptides with MW 138 kD, 132 kD and a minor peptides of 65 kD. The coalponents of Tm13--14 crystal protein or its proteinase resistant peptides (PRPs) bygut juice of the three insect species tested are different from those of strain HD--1and 3370--1.The toxic PRPs of Tm13--14, resulted from dissolving crystal by gut juice ofthree insect species, were purified by two steps, first by sephadex G--100 and thenby DEAE--52 chromatography. The results of bioassay and SDS-PAGE analysis suggested that the toxic PRPs to the larvae of Bombyx mori were 68.5 and 59 kD, to thelarvae of Spodoptera litura were 71 kD, 65 kD and 59.6 kD, to the larvae of Epilqchna niponica were 69kD and 65 kD.The LC50 values of intact crystal, the first purified toxic PRPs and 2nd purifiedtoxic PRPs of Tm13--14 to the second instar larvae of E. niponica were 9.4, 4.1and 3.2 μg/ml respectively.
出处
《昆虫学报》
CAS
CSCD
北大核心
1995年第2期138-145,共8页
Acta Entomologica Sinica
基金
国家自然科学基金
国家85-10-02课题资助
