Studies upon DNA synthesis during multiplicity reactivation of T2r^+ bacteriophage

Abstract

Studies of the synthesis of bacteriophage T2r^+ deoxyribonucleic acid (DNA) in bacterial cells multiply infected with either ultraviolet (uv)-irradiated or normal T2r^+ particles indicate that there is a lag of 8–10 minutes in the production of viral DNA in the former case as compared to the latter. Premature lysis of the cells reveals that a similar 8–10 minute lag is present in the appearance of active intracellular phage in these instances. This result is observed using conditions in which multiplicity reactivation can be demonstrated. By using 5-methyltryptophan as an inhibitor of protein synthesis in cultures of phage-infected cells, it was determined that protein synthesis is necessary soon after infection with uv-irradiated as well as with unirradiated T2r^+ in order for production of phage DNA to take place. Protein synthesis is necessary for the initiation of DNA synthesis, but not for its continuation. Evidence was obtained that some of the steps in the multiplicity reactivation process, subsequent to the initial steps, may not require protein synthesis.