Screening for Bacillus subtilis mutants deficient in pressure induced spore germination: identification of ykvU as a novel germination gene

Exposure to high pressure induces germination in spores of Bacillus subtilis. To investigate the mechanisms of this process and to compare the pressure and nutrient induced germination pathways, a random transposon knock-out library of B. subtilis was constructed and screened for clones with a compromised pressure induced germination at 100 MPa. Two mutants were isolated and their transposon insertion was mapped to gerAC and ykvU respectively. While GerAC is required for production of the l-alanine receptor which has been implicated in pressure-induced germination before, YkvU is shown here to be a novel germination determinant in B. subtilis, affecting germination by high (100 MPa) and very high (600 MPa) pressure, by nutrients and by dodecylamine, but not by Ca2+-dipicolinic acid.