【摘要】 利用PCR技术扩增了粉纹夜蛾(Trichoplusia ni)颗粒体病毒增效基因全长片段,扩增产物用EcoRⅠ/HindⅢ双酶消化,经0.7%低熔点琼脂糖凝胶电泳纯化后插入pRSET-B中,得重组表达质粒pRSET/enhancin;但重组子生长异常,在IPTG诱导下未能明显表达目标蛋白.用PstⅠ/HindⅢ双酶消化pRSET/enhancin,电泳回收2.7kb片段后插入pQE-30中,得重组表达载体pQE/enhancin;在IPTG诱导下于35℃成功表达出分子量(Mr)约为108×103的融合蛋白并命名为P108.初步纯化的P108显示了极显著的增效活性,对棉铃虫核型多角体病毒感染棉铃虫3龄幼虫的7d致死率提高34.03%,LT50缩短1.4d;对苏云金杆菌杀棉铃虫3龄幼虫的72h致死率提高65.96%.图4表2参14更多还原

【Abstract】 A span enhancin gene of Trichoplusia ni granulovirus was amplified by PCR and cloned into pRSET-B vector successfully. The recombinant vector pRSET/enhancin, however, failed to express foreign protein in Escherichia coli BL21 (DE3). The 2.7 kb target gene was then retrieved by 0.7 low melt point temperature agarose from pRSET/enhancin digested by PstⅠ and HindⅢ, and inserted into pQE-30 vector and expressed successfully in M15 (pREP_ 4 ). The synergy of the expression product (P108) on Helicoverpa armigera nuclear polyhedrosis virus (HaNPV) and Bacillus thuringiensis (Bt) against the 3~ rd instar larvae of cotton bollworm, H. armigera, was studied. The results indicated that the accumulated mortality of the larvae was increased by 34.03 on the 7~ th day post-infection and the median lethal time decreased by 1.4 days in HaNPV+P108 treated compared with that in HaNPV treated, and the mortality in 72 h increased by 65.96 in Bt+P108 treated compared with that in Bt treated. Fig 4, Tab 2, Ref 14更多还原