Abstract
Bacteriophage R17 and a series of amber mutants of R17 were used to infect cultures of Escherichia coli. The ribonucleic acid (RNA) of these cultures was radio-actively labeled, extracted, and subjected to polyacrylamide gel electrophoresis. Synthesis of ribosomal RNA was inhibited in cultures infected with the wild-type R17 and in cultures infected with phage mutants retaining the ability to produce viral polymerase. With the exception of one mutant tested, the degree of inhibition of ribosomal RNA synthesis in infected cells was correlated with the amount of viral polymerase synthesized. Maturation of 16S ribosomal RNA from its 17S RNA precursor appeared normal in infected cells, indicating that the inhibition of 16S ribosomal RNA synthesis occurred solely at the transcriptional level.