Extracellular exonuclease as a stage 0 biochemical marker in Bacillus subtilis sporulation

Calcium-dependent exonuclease activity was produced by sporulating cells of Bacillus subtilis 168. Nuclease activity was released into the culture medium at approximately the same time as sporulation proteases, and production of these enzymes was tied to DNA replication. Results suggest that nuclease production is a function of the spo0H locus.