Genes required for cytosolic survival are also required for virulence. (A) Bacteriolysis mutants (MOI of 0.2) were grown in bone marrow-derived macrophages (BMDMs) and then enumerated for CFU at 2 and 5 h postinfection. Data are calculated as fold change between 2 and 5 h and representative of four independent experiments. (B) L. monocytogenes bacteriolysis mutants (MOI of 0.5) were examined for plaque formation in L2 fibroblasts 6 days postinfection. Data are normalized to wild-type plaque size and represent means ± SEM of results from three independent experiments. ND, not detected. (C) Bacterial burdens (CFU) from the spleen (●) and liver (□) were enumerated at 48 h postinfection. Data are representative of results from two biological replicates. The horizontal dotted and solid lines denote the limits of detection for the spleen and livers, respectively. Mann-Whitney statistical analysis was performed to measure statistical significance in comparison to wild-type results.