Fig. 5

Expression of HtrA and HtrB upon AmyE or AmyL production. Wild-type cells producing AmyE or AmyL were separated from the growth medium by centrifugation after 16 h of growth in MBU medium at 37 ℃. Subsequently, proteins in the cells and growth medium fractions were separated by LDS-PAGE, and visualized with SimplyBlue SafeStain as described for Figure 1 (upper panel). The presence of HtrA and HtrB in the cell and growth medium fractions was analyzed by Western blotting using polyclonal antibodies against HtrA (middle panel) or HtrB (lower panel). The extracellular proteolytically processed forms of HtrA and HtrB are marked with a star. Major cell-associated degradation products are marked with a ‘D’. Molecular weights of marker proteins are indicated (in kDa) on the left side of each gel and Western blot