FIGURE 6.

PknB extracellular PASTA domains are essential for cell survival. A, schematic representation of PknB PASTA domain deletion mutations. B, mc²ΔpknB was transformed with pNit, pNit-PknB, pNit-PknB-PASTA1, pNit-PknB-PASTA2, or pNit-PknB-PASTA3 and were seeded at an A₆₀₀ of 0.2 for 6 h. WCLs from these strains grown in the presence/absence of ATc and in the presence of 0.2 μm IVN in the case of mc²ΔpknB harboring deletion constructs were probed with α-PknB and α-GroEL1 antibodies. Arrows, bands corresponding to PknB deletion mutants. C, growth pattern analysis of mc²ΔpknB transformant strains in the absence of ATc. 0.2 μm IVN was added to mc²ΔpknB strains harboring pNit vector or PknB-PASTA1, -2, or -3 constructs. Cultures were seeded at an initial A₆₀₀ of 0.02. D, Rv-pptr-B transformants were seeded at A₆₀₀ of 0.2. WCLs prepared from different Rv-pptr-B transformants grown in the absence or presence of 0.2 μm IVN were resolved and probed with α-PknB and α-GroEL1 antibodies. Arrows, bands corresponding to PknB deletion mutants. E, growth pattern analysis of the Rv-pptr-B transformants in the absence of pristinamycin. All of the cultures were seeded at an initial A₆₀₀ of 0.1. Error bars, S.E.