[Ultrastructure of the intracellular development of bacteriophage phi C 31]

The intracellular development of the bacteriophage phi C31 in thermally induced cultures of the lysogen Streptomyces coelicolor 01 changes remarkably its cell structure. At 10 min post-induction, a big number of mesosomes are shown by the cells. At 30 min post-induction, the cytoplasm contains capsids which are still empty. At the end of the latent period mature virions are shown and immediately after, cell lysis occurs through the tip of germinative tubes. In old cultures (10 h or more) no viral progeny is detected. However, when the amino acid glycine is added to the culture medium, new virions are seen, but in smaller number than in germinating cultures. These results seem to indicate that the lysis happens at the tip of the germinative tubes probably because this is an area weakened by the preferential growth that takes place on it.