Induction of prophage in Streptococcus lactis C2 by ultraviolet irradiation.

Streptococcus lactis C2 has been used extensively by many laboratories in studies on the metabolism of lactic streptococci. By using ultraviolet irradiation as the inducing agent, this organism was shown to release a small bacteriophage, indicating that it is a lysogenic strain. The induced phage had a head approximately 40 nm in diameter and a tail length and width of about 180 and 6 nm, respectively. A structure resembling a collar was observed. Attempts to isolate a sensitive indicator strain for the virus were unsuccessful.