Sköld and Buchanan(1) have reported that there is a rapid loss of
RNA polymerase activity in Escherichia coli B after
infection with T4 bacteriophage. More recent studies on the mechanism of this inactivation have been made in this(2) and other laboratories.(3, 4) In this communication, we report the observation of a transient stimulation of
RNA polymerase activity when measurement is made immediately after
infection and when cells are ruptured by a gentle lysis procedure. The increase in activity is independent of the synthesis of
protein. The activity in the extracts of infected cells is lost by treatment of the extract with antibody to E. coli
RNA polymerase and is refractive to the inhibitory action of the
antibiotic rifamycin. Hybridization experiments indicate that an
RNA transcribed almost exclusively from a T4
DNA template is the product of incubation of extracts of infected cells with a reaction mixture containing an exogenous primer (salmon sperm
DNA). These findings are consistent with the hypothesis that one of the first steps in phage
infection is the formation of a transcription complex containing T4
DNA and E. coli
RNA polymerase.