Macromolecular synthesis in mycobacteriophage I3 infected cells

DNA-, RNA- and protein synthesis have been studied in Mycobacterium smegmatis cells infected with phage I3. The macromolecular synthesis continued until the end of latent period. Early RNA and protein synthesis were necessary prior to the commencement of DNA replication. The infecting phage DNA sedimented as larger than unit length of genome, after initiation of DNA synthesis. Although the host DNA was not degraded, 90 percent of the RNA synthesized after phage infection hybridized to phage DNA.