Aims: To measure rates of release of small molecules during pressure germination of Bacillus subtilis spores, and the role of SpoVA proteins in dipicolinic acid (DPA) release.
Methods and results: Rates of DPA release during B. subtilis spore germination with pressures of 150 or 500 megaPascals were much higher in spores with elevated levels of SpoVA proteins, and spores with a temperature-sensitive mutation in the spoVA operon were temperature-sensitive in DPA release during pressure germination. Spores also released arginine and glutamic acid, but not AMP, during pressure germination.
Conclusions: Pressure germination of B. subtilis spores causes release of many small molecules including DPA. SpoVA proteins are involved in the release of DPA, perhaps because SpoVA proteins are a component of a DPA channel in the spore's inner membrane.
Significance and impact of the study: This work provides new insight into the mechanism of pressure germination of spores of Bacillus species, a process that has significant potential for usage in the food industry.