FIG. 5.
In vivo competition between wild-type L. pneumophila and mutant NU243. A mixture of 130b and the Kmr mutant NU243 was introduced into the lungs of A/J mice by intratracheal inoculation. At 1 and 3 days postinoculation, the ratio of 130b to mutant in infected lungs was determined. Data are representative of the actual values obtained per mouse (n = 4), and a solid bar represents the mean value. The 130b to mutant ratio increased significantly between days 1 and 3 (Student's t test, P < 0.05).