Fig 1. A K88R mutation in RpsL allows L. pneumophila strain LPE509 to replicate in macrophages.
A. Intracellular growth of a spontaneous RpsLK88R mutant of strain LPE509 in primary macrophages. B. K43N mutations do not allow L. pneumophila to replicate in macrophages. Bone marrow-derived macrophages from A/J mice were challenged with indicated bacterial strains at an MOI of 0.05. After synchronization 2 hrs postinfection, total bacterial counts were determined by plating appropriately diluted saponin solubilized infected cells onto bacteriological medium. Infections were performed in triplicate and data shown were from one representative of five experiments with similar results. C. Schematic diagram of the positions of the K43N and K88R mutations in RpsL, n is the number of independent mutants examined.