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目的：克隆恶性疟原虫裂殖子表面蛋白２全基因，并在大肠杆菌中进行表达。方法：采用ＰＣＲ扩增恶性疟原虫ＦＣＣ－１／ＨＮ株 ＭＳＰ２基因，克隆插入 ｐＵＣ１９，并重组入表达质粒载体中，转化大肠杆菌，诱导重组质粒 ｐＢＫ－ＣＭＶ／ｍｓｐ２表达ＭＳＰ２蛋白，对表达产物进行ＳＤＳ－ＰＡＧＥ，ｄｏｔ－ＥＬＩＳＡ和Ｗｅｓｔｅｒｎ ｂｌｏｔ鉴定。结果：ＰＣＲ扩增出８２４ｂｐＤＮＡ片段，经酶切鉴定和部分序列测定证实为 ＭＳＰ２基因序列；表达产物的相对分子质量为 ３． ２ × １０~４，与 ＭＳＰ２的理论分子质量相符，用 ｄｏｔ－ＥＬＩＳＡ和 Ｗｅｓｔｅｒｎ ｂｌｏｔ均证实表达产物具有恶性疟原虫抗原表位。但表达产物的量较低，约占菌体总蛋白量的 １０％。结论：恶性疟原虫ＭＳＰ２基因可以在大肠杆菌中得到表达，但表达产物的产量有待进一步提高。
Objective: To clone Plasmodium falciparum merozoite surface protein 2 gene and express it in E. coli. Methods: MSP2 gene of Plasmodium falciparum FCC-1 / HN strain was amplified by PCR, cloned into pUC19, recombined into expression plasmid vector and transformed into E.coli. MSP2 protein was induced by recombinant plasmid pBK-CMV / msp2, SDS-PAGE, dot-ELISA and Western blot identification. Results: The 824bp DNA fragment was amplified by PCR. The MSP2 gene sequence was confirmed by restriction enzyme digestion and partial sequencing. The relative molecular mass of the expressed product was 3. 2 × 10 ~ 4, which was consistent with the theoretical molecular mass of MSP2. Both dot-ELISA and Western blot confirmed that the expressed product had the Plasmodium falciparum antigenic epitope. However, the amount of the expression product is lower, accounting for about 10% of the total amount of the bacterial protein. Conclusion: Plasmodium falciparum MSP2 gene can be expressed in Escherichia coli, but the yield of the expression product need to be further improved.