Clonging And High-level Expression Of Alpha-toxin Gene Of Clostridium Perfringens Type A And Its Immunization

α-toxin is the major pathogenic factor of Clostridium perfringens type A which can cause traumatic gas gangrene on peacetime or wartime. There are no effect method to therapy it now. For this study,we would clone whole α-toxin gene and make it expressed in Escherichia Coli and then we would study its bioactivity and immunogenicity.We amplified 1194bp CPA gene from the C57-1 strain which contains α-toxin gene, it was most similar to the α-toxin gene from Genebank. So it was the best gene material for next study.The pXETA02 strain could express α-toxin protein specifically which was detected by ELISA experiment. Then we optimized the expression conditions. When induced by IPTG, the recombinant α-toxin product could be highly expressed nearly 35% of somatic protein; When induced by lactose, the recombinant α-toxin product could be highly expressed nearly 23% of somatic protein. This experiment could be considered as the reference for producing recombinant α-toxin protein.Soon we studied the recombinant α-toxin bioactivity and its immunogenicity. The immunogenicity of the recombinant α-toxin was better and it had lost its toxicity. So the pXETA02 strain could be used for producing genetic engineering vaccine.The result of this study could be helpful for the next study of α-toxin gene mutation and multivalent vaccine preparation.