Hassan D M, Brevet J
Plasmid. 1983 Jul;10(1):31-44. doi: 10.1016/0147-619x(83)90055-0.
It is possible in two steps to insert into the plasmid RP4 two copies of the transposon Tn7. This was demonstrated using a wild-type Tn7 in the first step, and a Tn7 derivative (carrying an additional marker), in the second step. The two successive transpositions occurred with the same polarity and frequency. The genetic structures of the resulting plasmids, predicted from the phenotypes of the bacterial host, were confirmed by direct analysis of the plasmid DNAs. Thus, the phenomenon of cis-acting transposition immunity, described with Tn1 or Tn3, does not take place in the case of Tn7.
分两步将两个转座子Tn7拷贝插入质粒RP4是可行的。第一步使用野生型Tn7进行了验证，第二步使用了一个Tn7衍生物（携带一个额外的标记）。两次连续转座以相同的极性和频率发生。通过对质粒DNA的直接分析，证实了根据细菌宿主表型预测的所得质粒的遗传结构。因此，Tn7不存在如Tn1或Tn3所描述的顺式作用转座免疫现象。
