Yamamoto N, Droffner M L, Yamamoto S, Gemski P, Baron L S
J Gen Virol. 1985 Aug;66 ( Pt 8):1661-8. doi: 10.1099/0022-1317-66-8-1661.
phi 80immP22dis, a hybrid between phi 80 and P22, carries all the late genes of phi 80 and most of the P22 early region including the immC and immI bipartite immunity loci. The presence of the immI region allows this hybrid to grow on lysogens of phi 80immP22 hybrids which have the immC locus, but not the immI locus. In addition to these P22 immunity regions, phi 80immP22dis contains the P22 att marker so that the prophage can be inserted into the chromosomal P22 attachment site adjacent to the proA-proB region of the host. Unlike its phi 80 parent which performs specialized transduction of the trp region, phi 80immP22dis transduces markers located adjacent to its attachment site to Escherichia coli K12 recipients at high frequencies (0.3% for argF and 0.18% for proA). Induction of phi 80immP22dis lysogens yields new hybrid phage clones which have incorporated E. coli K12 chromosomal segments in place of the P22 immI to att segment. Having lost the immI region, the new hybrids no longer grow in phi 80immP22 lysogens. These new hybrids, termed phi 80immP22dis-, possess specialized transducing properties, transferring the argF and proA markers at higher frequencies (21% for argF and 12% for proA) than previously obtained with the phi 80immP22dis phage.
phi 80immP22dis是phi 80和P22的杂交体，携带phi 80的所有晚期基因以及P22早期区域的大部分，包括immC和immI双分免疫位点。immI区域的存在使得这种杂交体能在具有immC位点但没有immI位点的phi 80immP22杂交体的溶原菌上生长。除了这些P22免疫区域外，phi 80immP22dis还含有P22附着标记，因此原噬菌体可以插入到宿主proA - proB区域附近的染色体P22附着位点。与其进行trp区域特异性转导的phi 80亲本不同，phi 80immP22dis能以高频率（argF为0.3%，proA为0.18%）将位于其附着位点附近的标记转导给大肠杆菌K12受体。诱导phi 80immP22dis溶原菌会产生新的杂交噬菌体克隆，这些克隆已将大肠杆菌K12染色体片段整合到P22 immI到att片段的位置。由于失去了immI区域，新的杂交体不再能在phi 80immP22溶原菌中生长。这些新的杂交体，称为phi 80immP22dis -，具有特异性转导特性，转移argF和proA标记的频率（argF为21%，proA为12%）高于之前用phi 80immP22dis噬菌体获得的频率。
