FIG. 3.

Pro-ς^K processing during spore formation. Sporulation was induced in wild-type and mutant cells, and at the indicated times, samples were removed, cell extracts were prepared, and proteins were size fractionated by SDS–12% PAGE and then probed with a polyclonal antiserum to pro-ς^K. Panels A and B show 10-min time points taken between 3 h and 4 h 10 min for cells carrying semiconservative (A) or nonconservative (B) changes in the spoIVB PDZ domain. The strains used were NH578 (spoIVB⁺), NH577 (spoIVBΔ::spc), NH685 (spoIVBGA114), NH987 (spoIVBGA126), NH587 (spoIVBGA144), NH573 (spoIVBND155), NH990 (spoIVBRK185), NH687 (spoIVBGA144/ND155), NH1001 (spoIVBGQ114), NH1003 (spoIVBGQ126), NH1005 (spoIVBGQ144), NH1007 (spoIVBNY155), and NH991 (spoIVBRH185). Panel C shows a similar immunoblot but using 30- or 60-min sampling between 3 and 8.5 h for spoIVB, spoIVBΔ::spc, and spoIVBDN149 (NH1135) cells. In each panel, the onset of pro-ς^K processing is indicated by an arrow.