User:Adam micro/sandbox

1st Source was used for rightward transcription. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4424060/

Rightward transcription expresses the O, P and Q genes. O and P are responsible for initiating replication, and Q is another antiterminator that allows the expression of head, tail, and lysis genes from PR’.

Pr promotor have been found to activate the origin in the use of rightward transcription, but the whole picture of this is still somewhat misunderstood. Given there are some caveats to this, for instance N15 phage may encode for DNA polymerase. Another example is the  P22 phage may replace the p gene which encodes for an essential replication protein for something that is capable of encoding for a DnaB helicase.