To determine the minimal active fragment of Cry1Ba3 protein, nine different fragments of cry1Ba3 gene were amplified using PCR, and then were expressed in E. coli BL21 respectively.

• 为了确定Cry1Ba3的最小活性区,通过PCR扩增获得9种不同长度的cry1Ba3基因片段,分别在大肠杆菌BL21中表达。