Construction of derivatives of the F plasmid pOX-tra715: Characterization of traY and traD mutants that can be complemented in trans
Construction of derivatives of the F plasmid pOX-tra715: Characterization of traY and traD mutants that can be complemented in trans
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DOI：
10.1046/j.1365-2958.1996.00087.x
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发表时间：
1996-10-01
影响因子：
3.6
通讯作者：
IppenIhler, K
中科院分区：
文献类型：
--
作者：
Maneewannakul, K;Kathir, P;IppenIhler, K
F质粒的衍生物pOX 38-tra 715从来自噬菌体T7的外源启动子（P-T7）表达整个F tra操纵子。构建了一系列与pOX 38-tra 715相关的质粒，其在traY中携带缺失突变或点突变。当P-T7启动子被诱导时，这些质粒表达F菌毛，但是是转移缺陷的，除非TraY是从相容质粒反式提供的。在含有野生型P-Y启动子的pOX 38质粒的traY基因中插入卡那霉素抗性盒，导致F纤毛形成和转移能力的丧失。在反式中引入TraY部分地恢复了纤毛形成和转移，这表明TraY在正调节P-Y启动子中具有作用。构建了pOX 38-fra 719-traD 411，其含有氯霉素抗性盒代替pOX 38-tra 715中的卡那霉素抗性盒和traD突变，以证明该系列质粒在研究长（30 kb）F tra操纵子中的实用性。
A derivative of the F plasmid, pOX38-tra715, expresses the entire F tra operon from a foreign promoter (P-T7) derived from phage T7, A series of plasmids related to pOX38-tra715 were constructed which carry either deletion mutations or point mutations in traY. When the P-T7 promoter was induced, these plasmids expressed the F pilus but were transfer deficient unless TraY was supplied in trans from compatible plasmids. Insertion of a kanamycin-resistance cassette in the traY gene of the pOX38 plasmid, which contains the wild-type P-Y promoter, resulted in loss of F piliation and transfer ability. Introduction of TraY in trans partially restored piliation and transfer suggesting that TraY has a role in positively regulating the P-Y promoter. pOX38-fra719-traD411, which contains a chloramphenicol-resistance cassette in place of the kanamycin-resistance cassette in pOX38-tra715 and a mutation in traD, was constructed to demonstrate the utility of this series of plasmids in studying the long (30 kb) F tra operon.