猪胸膜肺炎放线杆菌ApxⅡ截短蛋白在大肠杆菌中的表达和优化

Porcine contagious pleuropneumonia (PCP) caused by Actinobacillus pleuropneumonia(APP) is a common swine infectious disease that have caused significant losses to the swine industry. The APP toxin ApxⅡ has shown good immune activity and The recombinant subunit vaccine composed of ApxⅡ can eExpression and optimization of ApxⅡ truncated protein of Actinobacillus pleuropneumoniae in Escherichia coliffectively prevent the outbreak of PCP. In this experiment, ApxⅡ recombinant plasmid was constructed in Escherichia coli and soluble expression was carried out, and its fermentation conditions were optimized in the well plate. On this basis, the culture was scaled up, and the key parameters, including temperature, pH and DO were optimized in a 5L fermenter, and under optimal conditions, the soluble expression level of ApxⅡ reached 1.5g/L, the highest level reported so far. The purified ApxⅡ could react specifically with the positive serum of porcine contagious pleuropneumonia, which proved its good immune activity. This experiment realized the high-efficiency soluble expression of ApxⅡ in Escherichia coli, and provided a method and research basis for its further expanded production.)