Cloning, Expression And Bioassay Of Cry 2Axm Protein With And Without Tag In Escherichia Coli

Purified proteins are highly unstable and will lose its biological activity if not frozen/stored properly. Naturally, every biological system has its own protective mechanisms to maintain the biological function of each protein such as chaperones. In this study, a chimeric Cry 2Axm gene from Bacillus thuringiensis (Bt) was isolated and transformed into Escherichia coli with and without His tag and T₇ tag to know the expression pattern and stability of the transgene. The experimental results revealed that the tagged recombinant given more protein compared with non tagged system. This study shows the positive role of fusion tags on protection and expression of the recombinant protein. Bioassay result showed 100% mortality for the 2Axm protein without tag and 70% mortality for the 2Axm protein with tag for both Helicoverpa armigera and Spodoptera litura. This result indicates tagging Cry 2Axm protein has some masking effect on the solubility and activity of the recombinant protein