Donoghue D J, Sharp P A
J Bacteriol. 1978 Dec;136(3):1192-6. doi: 10.1128/jb.136.3.1192-1196.1978.
A phage-plasmid hybrid was constructed for use as a recombinant DNA vector, allowing the propagation of cloned EcoRI restriction endonuclease fragments of about 2 X 10(6) to 11 X 10(6) daltons. The colicin E1 plasmid replicon was fused to the left arm of a lambdagt generalized transducing phage with a thermolabile repressor, yielding a genome which could be replicated either by phage lambda functions or via the colicin E1 plasmid replicon. At the nonpermissive temperature, phage functions were derepressed and phage growth occurred lytically. Alternatively, at the permissive temperature, lambda functions were repressed and the vector replicated as a covalently closed circular plasmid. The phage-plasmid hybrid vector could be maintained at a copy number determined by the colicin E1 plasmid replicon and was also sensitive to amplification after chloramphenicol treatment. An EcoRI fragment of Escherichia coli DNA encoding genes of the arabinose operon also was inserted into the central portion of the vector.
构建了一种噬菌体 - 质粒杂合体用作重组DNA载体，可用于克隆约2×10⁶至11×10⁶道尔顿的EcoRI限制性内切酶片段。将大肠杆菌素E1质粒复制子与带有温度敏感型阻遏物的λgt广义转导噬菌体的左臂融合，产生的基因组既可以通过λ噬菌体功能进行复制，也可以通过大肠杆菌素E1质粒复制子进行复制。在非允许温度下，噬菌体功能去阻遏，噬菌体生长呈裂解性。另外，在允许温度下，λ噬菌体功能被阻遏，载体作为共价闭合环状质粒进行复制。噬菌体 - 质粒杂合载体可以以由大肠杆菌素E1质粒复制子决定的拷贝数维持，并且在氯霉素处理后也对扩增敏感。编码阿拉伯糖操纵子基因的大肠杆菌DNA的EcoRI片段也被插入到载体的中央部分。
