恶性疟原虫丝氨酸重复抗原基因在大肠杆菌中的表达

采用 PCR方法特异性扩增恶性疟原虫云南株 (PFD- 3/ YN)丝氨酸重复抗原基因片段 ,经基因序列测定后克隆于 p GEX- 4T- 1融合蛋白表达载体 ,并转化大肠杆菌 TG1。SERA基因与 p GEX- 4T- 1重组后能在大肠杆菌 TG1中表达一 45 KDa的融合蛋白 ,当工程菌 OD5 90 为 0 .8～ 1.0时 ,加入终浓度 1m mol/ L IPTG进行诱导 ,表达量较高。采用 dot- EL ISA对表达产物进行鉴定。结果表明 SERA融合蛋白能被抗 SERA单克隆抗体所识别。

THE EXPRESSION IN E.COLI OF THE SERINE-REPEAT ANTIGEN GENE FROM PLASMODIUM FALCIPARUM

The serine repeart antigen gene fragment of the plasmodium falciparum PFD-3/YN(Yunan of China) was amplified by polymerase chain reaction.After the gene sequencing,the gene fragment was cloned into pGEX-4T-1 vector for expression of fusion protein with Glutathion S transferase.The recombinant plasmid pGEX SERA was transformed into the E.coli strains TG1.The recombinant plasmid could be induced to express a 45KDa fusion protein in E.coli after serine repeat antigen gene fragment recombined with pGEX-4T-1 vector.The fusion protein was expressed at high level when the bacterium were culture until the OD 590 reached 0 8~1 0 and added IPTG to a final concentration of 1mmol/L.Using dot ELISA to identify the expression products,the results indicated that expressed fusion protein could react specifically with monoclonal antibody against SERA.