Fig 5.

Western blot analysis of levels of overexpression of GerAA, GerAC, and GerBC from PsspD and PsspB. Spores of strains PS533 (wild-type [wt]), PS3476 (↑gerA), and FB58 (↑↑gerB) were prepared and purified, and the inner membrane fractions were isolated as described in Materials and Methods. The protein concentrations in the inner membrane fractions were determined such that the 1× amount of each one was identical and represented the inner membrane protein from ∼0.5 mg dry spores. Various amounts of inner membrane protein were analyzed on the same Western blot as probed with anti-GerAA serum and then stripped and reprobed with anti-GerAC serum to determine levels of overexpression of GerAA and GerAC in spores of the ↑gerA strain in which the gerA operon is under PsspD control. Various amounts of inner membrane protein were also analyzed on another Western blot probed with anti-GerBC serum to determine the level of overexpression of GerBC in spores of the ↑↑gerB strain, in which the gerB operon is under PsspB control.