Transposition of a plasmid deoxyribonucleic acid sequence that mediates ampicillin resistance: independence from host rec functions and orientation of insertion
Transposition of a plasmid deoxyribonucleic acid sequence that mediates ampicillin resistance: independence from host rec functions and orientation of insertion
复制标题
介导氨苄青霉素抗性的质粒脱氧核糖核酸序列的转座：独立于宿主rec功能和插入方向
DOI：
10.1128/jb.128.1.425-434.1976
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发表时间：
1976
影响因子：
3.2
通讯作者：
S. Falkow
中科院分区：
文献类型：
--
作者：
C. Rubens;F. Heffron;S. Falkow
在5.5 x 10（6）-道尔顿质粒RSF 1010上至少19个位点插入指定TEM β-内酰胺酶（TnA）的转座脱氧核糖核酸序列。有没有显着差异的频率转座或在分布的TnA插入位点的重组质粒分离重组熟练（rec+）或重组缺陷（rec-）的细菌宿主细胞。通过异源双链分析和限制性内切酶酶切确定TnA插入的位点和方向。插入编码磺胺类药物抗性的基因发生在两个不同方向的一个或另一个没有环形排列。P方向的插入对远端基因表达具有强极性，而M方向的插入具有致突变性但不具有极性。此外，我们已经观察到，TnA元素从不同的R质粒显示精细的结构异质性，并在复制起点附近的位点插入TnA导致质粒拷贝数的增加。
Insertion of the transposable deoxyribonucleic acid sequence that specifies the TEM beta-lactamase (TnA) occurred in at least 19 sites on the 5.5 x 10(6)-dalton plasmid RSF1010. There was no significant difference in the frequency of transposition or in the distribution of TnA insertion sites for recombinant plasmids isolated from recombination-proficient (rec+) or recombination-deficient (rec-) bacterial host cells. The site and orientation of TnA insertions were determined by both heteroduplex analysis and enzymatic digestion with restriction endonucleases. Insertion in the gene encoding for sulfonamide resistance occurred without circular permutation in one or the other of two distinct orientations. Insertions in orientation P were strongly polar on distal gene expression, whereas insertions in orientation M were mutagenic but not polar. In addition, we have observed that TnA elements from different R plasmids show fine structural heterogeneity, and that TnA insertion at a site adjacent to the origin of replication causes an increase in plasmid copy number.