γ-Aminobutyric Acid as a Required Germinant for Mutant Spores of Bacillus megaterium

Abstract

Germinated spores of Bacillus megaterium QM B1551 were irradiated with ultraviolet light, and spore-forming survivors were screened for germination requirements. Spore strains which failed to germinate in a variety of defined solutions germinative for spores of the parent strain were obtained. Mutant spores germinated readily in solutions containing yeast extract or one of numerous complex preparations. γ-Aminobutyric acid, obtained from yeast extract by column chromatography, was shown to be required for germination by the mutant spores. γ-Aminobutyric acid and l -alanine at final concentrations of 1 m m each, in solutions of KI (40 m m ), equaled the potency of yeast extract (1 mg/ml) in the germination of the mutant spores. One of several other amino acids could be substituted, though less effectively, for l -alanine. α-Aminobutyric acid, β-aminobutyric acid, β-alanine, and 5-aminovaleric acid were ineffective substitutes for γ-aminobutyric acid in mutant spore germination.