de Lorenzo V, Herrero M, Neilands J B
Department of Biochemistry, University of California, Berkeley 94720.
Mol Gen Genet. 1988 Aug;213(2-3):487-90. doi: 10.1007/BF00339620.
Genes determining the high affinity iron transport system mediated by the siderophore aerobactin are flanked in the enterobacterial plasmid pColV-K30 by inverted repeats of IS1 sequences, suggesting that the aerobactin genes are part of a transposon. To study this possibility, the entire region between the two IS1 sequences was cloned as an 18 kb HindIII-BamHI restriction fragment in pUC8 giving plasmid pMO1. A number of derivatives of pMO1, in which aerobactin genes were tagged with a kanamycin resistance gene, were prepared in order to assess the ability of both IS1s to promote the formation of cointegrates with pCJ105, an F derivative devoid of insertion sequences. Mating-out assays indicated that both flanking IS1s were active in cointegrate formation at detectable frequencies. In some cases, the cointegrates could be resolved, the final result being a transposition-like event for the entire aerobactin system.
决定由铁载体气杆菌素介导的高亲和力铁转运系统的基因，在肠杆菌质粒pColV-K30中位于IS1序列的反向重复序列两侧，这表明气杆菌素基因是转座子的一部分。为了研究这种可能性，将两个IS1序列之间的整个区域作为一个18kb的HindIII-BamHI限制性片段克隆到pUC8中，得到质粒pMO1。制备了许多pMO1的衍生物，其中气杆菌素基因用卡那霉素抗性基因进行了标记，以便评估两个IS1促进与pCJ105（一种不含插入序列的F衍生物）形成共整合体的能力。接合转移试验表明，两侧的IS1在可检测频率下均能促进共整合体的形成。在某些情况下，共整合体可以解离，最终结果是整个气杆菌素系统发生类似转座的事件。
