Computer simulation of T3/T7 phage infection using lag times.

A minimal mechanism is proposed which describes the transcriptional and translational processes for four phage proteins (RNA polymerase, DNase, primase and DNA polymerase) involved in T3/T7 DNA replication. Phage DNA replication is also included. It is shown how lag times may be incorporated into a kinetic mechanism. The distinct three-stage transport of phage DNA into the bacterial host (E. coli) is considered. DNA transport is assumed to be rate-determining for the transcription of class I and II proteins. Transcriptional and translational lag times have been calculated on the basis of available gene mapping of T7 phages. The kinetic behavior of T7 and T3 phage infection is practically identical. The hydrolysis of bacterial DNA by phage DNase (endonculease and exonuclease) as well as the subsequent phosphorylation to the deoxymononucleoside triphosphates are assumed to be rate-determining in phage DNA replication. Good agreement with experiment is obtained in our computer simulations.