FIG 3.

Levels of β-galactosidase from a B. subtilis strain containing a disA-lacZ fusion (A) and compartmental synthesis of DisA-GFP in B. subtilis sporangia (B to D). (A) B. subtilis strain PERM733 (disA-lacZ) was grown at 37°C in DSM, and the OD₆₀₀ was measured (●). Cell samples were collected during vegetative growth and at various times during sporulation and treated with lysozyme, and initial extracts were assayed for β-galactosidase (◊), as were extracts from initially lysozyme-resistant forespores (△), all as described in Materials and Methods. Values shown are averages of duplicate independent experiments ± standard deviations of the β-galactosidase specific activity. (B to D) B. subtilis strain PERM1008 (disA-gfp) was grown at 37°C in DSM. Cell samples collected 7 h after time zero (T₀) were processed and photographed under fluorescence microscopy as described in Materials and Methods. (B) Bright field; (C) GFP channel; (D) overlay of the two images. T₀ is the time when the slopes of the logarithmic and stationary phases of growth intersected. Arrows indicate mother cell (MC) and forespore (FS) compartments (B) and DisA-GFP (C).