Figure 1

Lytic bacteriophage life cycle. Lytic bacteriophages are viruses of bacteria with a life cycle similar to that of other organisms that breed only once, such as the agave plant or salmon. There are three main stages, analogous to the dispersal, growth, and reproductive periods in animals and plants. (1) Dispersal stage. The virus floats freely in the environment until it encounters a host, after which it has a chance to infect the host that is determined by the phage's adsorption constant. (2) Growth stage. The phage genome enters the cell and turns the infected host into a phage factory by creating viral components. During this period the initial phage virion is destroyed but no new ones have been generated. The end of this period, as the first viable progeny is created, is the eclipse time (E). (3) Adult stage. The rate of phage accumulation within the cell is approximately linear across diverse phage lineages [15, 18, 19], although in some cases, such as phage T3 and T7, production seems unable to continue indefinitely [20, 21]. This third stage continues until lysis (L), in which the phage bursts its host cell in order to escape it and infect new hosts. The period from first phage production to lysis is here called lysis interval. Lysis terminates phage production and initiates a new dispersal stage. Figure modified from [17].