On the basis of the holin-lysin data that suggest that lysis of the mutants is a rare event, we asked whether cytosolic survival correlates with intracellular replication. We first assessed intracellular replication in wild-type C57BL/6 bone marrow-derived macrophages (BMDMs) (Fig. 2A and Fig. S4A). pdhC::Tn mutants are gradually cleared over time, whereas yvcJ::Tn mutants displayed partial replication defects in macrophages, similarly to previous observations for ΔyvcK mutants (8). Other mutants did not display replication defects within macrophages, suggesting that bacteriolysis is incomplete and that intracellular bacteriolysis does not strictly correlate with intracellular replication. Although MK mutants could not grow in minimal media lacking MK, MK-deficient mutants grown in MK-limited media displayed a small but reproducible invasion defect, potentially due to decreased internalization or decreased phagosomal survival. In addition, and consistent with previous results (30, 31), MK-starved MK-deficient mutants were impaired for intracellular replication (Fig. S4B), suggesting that carryover of MK from brain heart infusion can support intracellular replication over the course of infection. Furthermore, while individual bacteriolysis mutants displayed differential growth phenotypes in a variety of cell types, the ability to replicate intracellularly did not correlate with cell type-specific lysis (Fig. S4C to E).