Schumann W
Gene. 1979 Apr;5(4):275-90. doi: 10.1016/0378-1119(79)90103-3.
The construction of three hybrid plasmids containing different parts of the left or immunity and end of phage Mu DNA is described. The recombinant plasmids pKN05 and pKN54 carry the HindIII.C and PstI.C fragments of Mu DNA, respectively. Neither of these plasmids expresses the killing function. Moreover, they do not allow plating of superinfecting Mu phages. Plasmid pKN62 harbors the fragment located in between the left PstI and EcoRI cleavage sites on Mu DNA, allows plating of superinfecting Mu phages, but does not express the killing function. These data suggest that the gene coding for the killing function is either positively regulated by a product from the EcoRI.C fragment, or the killing function requires a second product not coded for by pKN62. Mu Vir A- or Mu Vir B- phages are able to grow on bacteria harboring the recombinant plasmid pKN001 which carries the left and EcoRI-C fragment of Mu DNA. This indicates that the superinfecting phages can induce the corresponding gene functions from pKN001. No such induction could be detected in cells harboring the hybrid plasmids pKN05, pKN54 or pKN62.
本文描述了三种含有噬菌体Mu DNA左端或免疫区及末端不同片段的杂种质粒的构建。重组质粒pKN05和pKN54分别携带Mu DNA的HindIII.C和PstI.C片段。这两种质粒均不表达杀伤功能。此外，它们不允许超感染的Mu噬菌体进行平板培养。质粒pKN62含有位于Mu DNA上PstI和EcoRI切割位点之间的片段，允许超感染的Mu噬菌体进行平板培养，但不表达杀伤功能。这些数据表明，编码杀伤功能的基因要么受到EcoRI.C片段产物的正调控，要么杀伤功能需要一种不是由pKN62编码的第二产物。Mu Vir A或Mu Vir B噬菌体能够在携带重组质粒pKN001的细菌上生长，该质粒携带Mu DNA的左端和EcoRI-C片段。这表明超感染的噬菌体能够从pKN001诱导相应的基因功能。在携带杂种质粒pKN05、pKN54或pKN62的细胞中未检测到这种诱导。
