Fig 1.

C. perfringens GR mutants. (A) Arrangement of GR genes in various C. perfringens mutant strains. (B) Analysis of GerKC levels in total lysates of C. perfringens SM101 (wild-type [WT]) and DPS119 (ΔgerKA) spores. Spores were decoated and lysed, and various amounts of protein in the total lysates from the spores of the two strains were run on SDS-polyacrylamide gels, followed by Western blotting using GerKC antibody, as described in Materials and Methods. The intensity of the GerKC band in the DPS119 lysate was compared to the intensities of bands given by various amounts of GerKC in the SM101 lysate (1× corresponds to the same amount of spores, ∼1.5 × 10⁷, in the two fractions). Analysis of the various band intensities by ImageJ gave a value for the GerKC level in DPS119 spores that was 12% of that in SM101 spores. The two bands above the GerKC band are likely bands that reacted nonspecifically, since their intensities were greatly increased relative to the intensity of the GerKC band in the DPS119 spores.