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研究了百日咳杆菌毒素Ｓ１亚单位与谷胱甘肽Ｓ－转移酶融合蛋白（ＧＳＴ－Ｓ１）在大肠杆菌（Ｅ．ｃｏｌｉ）中的表达，并一步纯化了重组ＧＳＴ－Ｓ１。首先用聚合酶链反应（ＰＣＲ）扩增出长度为５６０ｂｐ的编码百日咳毒素Ｓ１亚单位的ＤＮＡ片段。该片段比原编码Ｓ１蛋白的ＤＮＡ片段在其３′端缺失了１３８个碱基，将其按正确的阅读框克隆入质粒ｐＧＥＸ中ＧＳＴ基因的３′端，构成ＧＳＴ－Ｓ１融合基因表达载体ｐＧＥＸ－Ｓ１。经异丙基硫代－β－Ｄ－半乳糖苷（ＩＰＴＧ）诱导表达和十二烷基磺酸钠－聚丙烯酰胺凝胶电泳（ＳＤＳ－ＰＡＧＥ），可见所表达的ＧＳＴ－Ｓ１融合蛋白存在于细菌上清，为可溶性蛋白。分子量为４９ｋｕ处有明显的蛋白表达带。用谷胱甘肽（ＧＳＨ）亲和层析系统，一步纯化出ＧＳＴ－Ｓ１融合蛋白。最后经凝血酶的消化，得到２３ｋｕ的重组百日咳杆菌毒素Ｓ１亚单位蛋白。为百日咳疫苗的发展提供了依据
The expression of pertussis toxin S1 subunit and glutathione S-transferase fusion protein (GST-S1) in E. coli was studied and the recombinant GST-S1 was purified in one step. First, a 560bp DNA fragment encoding pertussis toxin S1 subunit was amplified by polymerase chain reaction (PCR). This fragment was 138 bp shorter than the original encoding S1 protein in its 3 ’end. The fragment was cloned in the correct reading frame into the 3’ end of the GST gene in plasmid pGEX to construct the GST-S1 fusion gene expression vector pGEX -S1. The expression of the expressed GST-S1 fusion protein was observed by isopropylthio-β-D-galactoside (IPTG) induction and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) In bacterial supernatant, soluble protein. Molecular weight of 49ku Department has obvious protein expression zone. The GST-S1 fusion protein was purified in one step using the glutathione (GSH) affinity chromatography system. Finally, digestion with thrombin resulted in 23 ku of recombinant pertussis toxin S1 subunit protein. Provided the basis for the development of pertussis vaccine