Streptomyces cell death, which occurs as the bacteria develop fruiting bodies and form spores, has been dismissed as nonspecific autolysis caused by cell wall degradation. Now Miguélez et al. (page ) show that the cell death is complex: it occurs at two different times in two different locations and as a series of defined steps that leave the cell wall intact.
Streptomyces grow first along and through their growth medium, as multinucleoid hyphae. This substrate mycelium subsequently forms stalks that rise above the growth medium. Parts of the aerial hyphae septate to form spores.
Cell death occurs in two major waves. As aerial hyphae are growing, nucleoids at the level of the growth medium begin degenerating. Sporulation then starts, by which time the substrate mycelium is dead and a second death process is starting in the aerial hyphae, from the bottom up. Two days later all cells are either...
