Cry1Ia和Cry2Ab杂交分子的构建和表达

Construct and Expression of Hybrid Proteins of Cry1Ia and Cry2Ab

同源性较低的Cry杀虫蛋白之间的结构域交换突变体成功案例很少。选择2种氨基酸同源性很低且蛋白其他特点差异也较大的Cry2Ab和Cry1Ia为亲本,将它们的3个结构域(Domain I,II和III)互换,构建6种结构域交换突变体。将这些突变体在Bt菌株中表达,分析其表达稳定性,并比较不同温度条件下的表达情况。结果显示,6种突变体在28.5,32.0℃条件下,均能够稳定表达,且表达量较高。说明构建的6种突变体在Bt菌株中具有较好的表达稳定性,以此为基础可以进一步检测其杀虫活性等特性。

There are a few successful domain-exchange mutants deriving from different classes of Cry toxins. The paper constructed domain-exchange（domain I, II and lII） mutants using Cry2Ab and Cry lla as the parent proteins. The 6 mutants obtained were expressed in Bacillus thuringieusis stain in different temperature conditions（28, 32 ℃ ） and analyzed by SDS-PAGE. The result showed that all of mutants constructed in the study could be expressed steadily in high level at both expression conditions and could be further researched for their insecticidal activity.