FIG. 2.

srfA-lacZ expression in B. subtilis. The expression levels of srfA-lacZ in strains ATCC 6633 (A) and 168-8G5 (B), grown in rich medium (□), minimal medium (○), and sporulation medium (▵), are depicted. (C) Effects of various mutations on the expression of srfA-lacZ in B. subtilis ATCC 6633. The following cultures were grown in minimal medium: ▪, wild type; ○, ΔcomA mutant; ▵, ΔcodY mutant; ▴, Δspo0H mutant; and □, Δspo0K mutant. The time scales refer to hours before and after the transition from exponential to stationary-phase growth (defined as time zero). β-Galactosidase activities are presented in activity units per OD₆₀₀ unit.