Participation of the lytic replicon in bacteriophage P1 plasmid maintenance
Year: 1989
Type: article
Abstract: P1 bacteriophage carries at least two replicons: a plasmid replicon and a viral lytic replicon. Since the isolated plasmid replicon can maintain itself stably at the low copy number characteristic of intact P1 prophage, it has been assumed that this replicon is responsible for driving prophage replication. We provide evidence that when replication from the plasmid replicon is prevented, prophage replication continues, albeit at a reduced rate. The residual plasmid replication is due to incomplete repression of the lytic replicon by the c1 immunity repressor. Incomplete repression was particularly evident in lysogens of the thermoinducible P1 c1.100 prophage, whose replication at 32 degrees C remained almost unaffected when use of the plasmid replicon was prevented. Moreover, the average plasmid copy number of P1 in a P1 c1.100 lysogen was elevated with respect to the copy number of P1 c1+. The capacity of the lytic replicon to act as an auxiliary in plasmid maintenance may contribute to the extraordinary stability of P1 plasmid prophage.
Source: Journal of Bacteriology
Authors: M B Yarmolinsky, E B Hansen, S Jafri, D K Chattoraj
Institution: National Cancer Institute
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1960436286