为获取具有生物学活性的弓形虫 P30蛋白 ,采用定向克隆的方法 ,自行设计引物通过 PCR扩增得到 P30基因片段 ,用 Eco R 和 Sal 双酶切后 ,连接到同样双酶切的原核表达载体 (p BV2 2 0和 p MAL P2 )上 ,转化大肠杆菌 DH5 α,分别得到含重组质粒 p BV2 2 0 - P30和 p MAL P2 - P30的工程菌。扩菌提取质粒经过酶切分析和 PCR扩增鉴定后 ,证实 P30基因的两个原核表达载体构建成功 ,为其在原核系统中的表达作准备 In order to obtain the biologically active Toxoplasma gondii P30 protein, the P30 gene fragment was amplified by PCR using a directed cloning method. After digestion with Eco R and Sal, it was ligated into the prokaryotic expression vector (p BV2 2 0 and p MAL P2) were transformed into E. coli DH5 α to obtain the engineered bacteria containing the recombinant plasmids p BV2 2 0 - P30 and p MAL P2 - P30, respectively. Enzyme digestion analysis and PCR amplification showed that two prokaryotic expression vectors of P30 gene were successfully constructed and were ready for expression in prokaryotic system