| Abstract: | Chemical and physical stabilities of bacteriophages ?UW 21 and ?UW 51 infecting Micromonospora purpurea ATCC 15835 were examined. Both phages were stable over the pH range of 5 to 8 and to heating at temperatures up to 50 degrees C and especially stable in buffer containing magnesium ion. Exposure to 1 M Ca(NO3)2 inactivated both phages, and phage ?UW 51 was also susceptible to 1 M CaCl2, 0.1 M tris(hydroxymethyl)aminomethane, and 0.3% H2O2. Phage plating efficiency was highest on the cultures at logarithmic phase and sometimes much influenced by host growth. Phage ?UW 51 has a latent period of 2 h at 34 degrees C and a burst size between 35 and 40. The latent period for phage ?UW 21 is about 12 h, and the burst size is smaller than 30. |
