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利用大肠杆菌启动子探测质粒ｐＫＫ２３２－８为载体、用两组限制性内切酶ＢａｍＨＩ－ＳａｌＩ和ＨｉｎｄⅢ－ＳａｌＩ分别消化盐生盐杆菌Ｊ７（Ｈａｌｏｂａｃｔｅｒｉｕｍｈａｌｏｂｉｕｍ）的质粒ｐＨＨ２０５，在体外进行重组，转化Ｅ．ｃｏｌｉＨＢ１０１感受态细胞，在含氨苄青霉素和氯霉素的选择平板上筛选转化子，并从随机挑选的２０株转化子中，获得抗氯霉素水平达到１１０μｇ／ｍｌ的转化子Ｔ１和Ｔ２，所含重组质粒分别被命名为ｐＪＨ和ｐＪＢ。经限制性酶切分析及杂交分析表明，ｐＪＨ质粒上插入了一段来源于ｐＨＨ２０５质粒的ＤＮＡ片段，其大小为８００ｂｐ左右。通过重新转化实验进一步表明，该ＤＮＡ片段在大肠杆菌中具有启动子功能，从而证明，在古细菌（盐生盐杆菌）的质粒ＤＮＡ中存在具有真细菌（大肠杆菌）基因启动子活性的ＤＮＡ片段。
The plasmid pKK232-8 of Escherichia coli promoter was used as the vector to digest the plasmid pHH205 of Halobacterium halobium J7 with two sets of restriction enzymes BamHI-SalI and HindIII-SalI, respectively. coliHB101 competent cells were screened for transformants on ampicillin and chloramphenicol selection plates and transformants T1 and T2 resistant to chloramphenicol at a concentration of 110 μg / ml were obtained from randomly selected 20 transformants The recombinant plasmids were named pJH and pJB, respectively. Restriction enzyme digestion analysis and hybridization analysis showed that pJH plasmid was inserted into a DNA fragment derived from pHH205 plasmid with a size of about 800bp. It was further confirmed by the re-transformation experiment that this DNA fragment has promoter function in Escherichia coli, thereby confirming that a DNA fragment having the promoter activity of the eubacteria (E. coli) gene is present in the plasmid DNA of Archaea (Halobacterium salina) .