Garaev M M, Bobkov A F, Bobkova A F, Kalinin V N, Smirnov V D, Tikchonenko T I
Gene. 1982 Apr;18(1):21-8. doi: 10.1016/0378-1119(82)90052-x.
The formation of a deletion derivative of plasmid pBR322, designated pBR322 delta 1, was observed during cloning of various eukaryotic DNAs, when the BamHI site of the plasmid vector was used for construction of the recombinant molecules. The restriction analysis of six independently isolated pBR322 delta 1 plasmids allowed establishment of their complete identity. Similar deletion derivatives were also formed as a result of transformation of Escherichia coli cells by the linear form of vector pBR322 produced by BamHI cleavage, but not by SalI or HindIII. The endpoints of the deletion in one of the pBR322 delta 1 plasmids occurred at positions 375 and 16666 bp from the EcoRI site, as determined by sequence analysis. Formation of pBR322 delta 1 is most probably due to site-specific recombination between the sequence in the 1666-1670 bp region and the BamHI end of the linear pBR322 molecule. THe deletion was not controlled by the recA system of the host bacteria.
在使用质粒载体pBR322的BamHI位点构建各种真核DNA的克隆过程中，观察到了一种名为pBR322 delta 1的pBR322缺失衍生物的形成。对六个独立分离的pBR322 delta 1质粒进行的限制性分析确定了它们的完全一致性。由BamHI切割产生的线性载体pBR322转化大肠杆菌细胞也会形成类似的缺失衍生物，但SalI或HindIII切割产生的线性载体则不会。通过序列分析确定，其中一个pBR322 delta 1质粒的缺失端点位于距EcoRI位点375和16666 bp处。pBR322 delta 1的形成很可能是由于1666 - 1670 bp区域内的序列与线性pBR322分子的BamHI末端之间发生了位点特异性重组。这种缺失不受宿主细菌recA系统的控制。
