LYSOGENY 



327 



100 



200 



40 80 120 160 200 



Time in minutes 



Fig. 3. Phage multiplication after infection of sensitive Pseudomonas aeruginosa 13 

 with temperate phage P8« Bacteria are infected with a multiplicity of 5 phage particles 

 per cell. The optical density (Ciu've 1) and the relative number of infectious centers, 

 measured after premature lysis (Curve 2), and during spontaneous lysis (Curve 3), are 

 plotted versus the time of incubation at 37°C. after infection. (From Jacob and WoUman 

 1953.) 



40 80 120 160 200 



Time in minutes 



Fig. 4. Phage multiplication after U.V. induction of lysogenic Pseudomonas aeruginosa 

 13 (8). Bacteria are exposed to an optimal dose of UV light. The optical density (Curve 1) 

 and the relative number of infectious centers, measured after premature lysis (Curve 2) 

 and during spontaneous lysis (Curve 3) are plotted versus the time of incubation at 

 37°C. after irradiation. (From Jacob and Wollman, 1953.) 



