Apparent dependence of sporulation on synthesis of highly phosphorylated nucleotides in Bacillus subtilis

Bacillus subtilis contains an enzyme that synthesizes the highly phosphorylated nucleotide adenosine 5',3'(2')-bis(triphosphate), abbreviated p(3)Ap(3). This enzyme can be demonstrated to be present in the cytoplasmic membrane of B. subtilis at all stages of growth and development. During vegetative growth its enzymatic activity is inhibited by phosphorylated metabolites of energy-rich carbon sources, as was shown with the aid of conditional sporulation mutants. The finding that a temperature-sensitive sporulation mutant with a mutation in the spoOF gene, an early sporulation gene, shows a temperature-sensitive activity of p(3)Ap(3)-synthetase indicates that p(3)Ap(3) plays an important role in sporulation, probably initiation of sporulation.