Fig. 5. Cleavage of Pro-σ^K and levels of channel proteins in wild-type cells and mutants deficient in channel proteins.

B. subtilis strains engineered to produce Luc H245F in the MC or FS were starved to induce sporulation. At 2 h PS, culture aliquots were transferred to a 96-well plate. Samples collected from aliquots at the indicated times PS were subjected to immunoblot analysis using antibodies against SpoIVFA, SpoIVFB, Pro-σ^K, SpoIIIAH, and SpoIIQ. Representative immunoblots are shown for WT cells and null mutants of the indicated channel proteins. Similar results were observed for at least two biological replicates of strains producing Luc H245F in the MC or FS.