【Abstract】 PCR method was used to introduce the code sequence of Factor Xa cleavage site to the 5′ end of cecropin CMIV mutant gene X,then the gene was cloned into the expression vector pGEX KG,and was highly expressed in E.coli BL21 by IPTG induction.The fusion protein was purified by affinity chromatography and was cleaved by Factor Xa.Cecropin X with antibacterial activity was obtained after purified by ion exchange chromatography.更多还原