Growth of M. smegmatis is insensitive to the amount of expressed LigA. As shown in the panel on the right, optical density (OD) analysis determined the extent of growth of M. smegmatis strains carrying a natural level of LigA (lane 1, wt strain), a low level of LigA (lane 2, ΔligA-Pami ligAMs, without inducer), and an overproduced level of LigA (lane 3, ΔligA-Ptet ligAMs, with inducer). In the left panel, the level of LigA was determined by Western blot analysis with antibodies raised against LigA of M. tuberculosis. For each lane, 12 μg of total proteins was loaded.