Mutagenesis of the Tra1 core region of RK2 by using Tn5: identification of plasmid-specific transfer genes.
Mutagenesis of the Tra1 core region of RK2 by using Tn5: identification of plasmid-specific transfer genes.
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使用 Tn5 对 RK2 Tra1 核心区进行诱变：鉴定质粒特异性转移基因。
DOI：
10.1128/jb.171.7.4100-4103.1989
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发表时间：
1989
影响因子：
3.2
通讯作者：
Lanka,E
中科院分区：
文献类型：
--
作者：
Guiney,DG;Deiss,C;Simnad,V;Yee,L;Pansegrau,W;Lanka,E
IncP α质粒RK 2/RP 4的接合系统由指定为Tra 1、Tra 2和Tra 3的转移区编码。Tra 1核心区克隆在质粒pDG 4 delta 22上，由转移起点（oriT）和侧翼DNA的2.6个内切酶组成，提供IncP α质粒特异性功能，允许pDG 4 delta 22被异源IncP β质粒R751动员。pDG 4 delta 22中的Tn 5插入限定了oriT的质粒特异性转移所需的最小2.2-内切酶区域。Tra 1核心包含traJ和traK基因以及traJ下游的18千道尔顿开放阅读框。traJ和traK基因被证明是通过这些基因内插入物的互补进行转移所必需的。获得了18千道尔顿开放阅读框在转移中的作用的遗传学证据，尽管在细胞裂解物中尚未检测到这种蛋白质。这些研究表明，至少有三个转移蛋白参与质粒特异性相互作用在oriT。
The conjugation system of the IncP alpha plasmid RK2/RP4 is encoded by transfer regions designated Tra1, Tra2, and Tra3. The Tra1 core region, cloned on plasmid pDG4 delta 22, consists of the origin of transfer (oriT) and 2.6 kilobases of flanking DNA providing IncP alpha plasmid-specific functions that allow pDG4 delta 22 to be mobilized by the heterologous IncP beta plasmid R751. Tn5 insertions in pDG4 delta 22 define a minimal 2.2-kilobase region required for plasmid-specific transfer of oriT. The Tra1 core contains the traJ and traK genes as well as an 18-kilodalton open reading frame downstream of traJ. The traJ and traK genes were shown to be required for transfer by complementation of inserts within these genes. Genetic evidence for the role of the 18-kilodalton open reading frame in transfer was obtained, although this protein has not been detected in cell lysates. These studies indicate that at least three transfer proteins are involved in plasmid-specific interactions at oriT.