Site-specific recombination of bacteriophage P22 does not require integration host factor
Site-specific recombination of bacteriophage P22 does not require integration host factor
复制标题
DOI：
10.1128/jb.181.14.4245-4249.1999
复制
发表时间：
1999-07-01
影响因子：
3.2
通讯作者：
Gardner, JF
中科院分区：
文献类型：
--
作者：
Cho, EH;Nam, CE;Gardner, JF
通过λ和P22的位点特异性重组通过多蛋白-DNA复合物进行。整合宿主因子（IHF）通过诱导形成活性重组复合物所必需的DNA弯曲来促进λ位点特异性重组。针对IHF的突变体在支持λ位点特异性重组方面的能力比野生型细胞低1,000倍以上。尽管P22的attP区域含有强的IHF结合位点，但体内整合和切除频率的测量表明，感染P22的P22可以在不存在IHF的情况下进行位点特异性重组以达到其最大效率。此外，质粒整合测定显示整合重组在野生型和ihfA突变体细胞中同样良好地发生。在缺乏功能性IHF的情况下，P22整合重组在大肠杆菌中也是有效的。这些结果表明，在缺乏IHF的情况下，可以形成精通重组的核蛋白结构，或者另一种因子可以在复合物的形成中取代IHF。
Site-specific recombination by phages lambda and P22 is carried out by multiprotein-DNA complexes. Integration host factor (IHF) facilitates lambda site-specific recombination by inducing DNA bends necessary to form an active recombinogenic complex. Mutants tacking IHF are over 1,000-fold less proficient in supporting lambda site-specific recombination than wild-type cells.;Although the attP region of P22 contains strong IHF binding sites, in vivo measurements of integration and excision frequencies showed that infecting P22 phages can perform site-specific recombination to its maximum efficiency in the absence of IHF. In addition, a plasmid integration assay showed that integrative recombination occurs equally weil in wild-type and ihfA mutant cells. P22 integrative recombination is also efficient in Escherichia coli in the absence of functional IHF, These results suggest that nucleoprotein structures proficient for recombination can form in the absence of IHF or that another factor(s) can substitute far IHF in the formation of complexes.