Initiation of Spore Germination in Bacillus subtilis : Relationship to Inhibition of l -Alanine Metabolism

Abstract

The inhibitory effects of anthranilic acid esters (methyl anthranilate and N-methyl anthranilate) on the L-alanine-induced initiation of spore germination was examined in Bacillus subtilis 168. Methyl anthranilate irreversibly inhibited alanine initiation by a competitive mechanism. In its presence, the inhibition could be reversed only by the combined addition of D-glucose, D-fructose, and K+. Both L-alanine dehydrogenase and L-glutamate-pyruvate transaminase, enzymes which catalyze the first reaction in L-alanine metabolism, were competitively inhibited by methyl anthranilate. The K1 values for germination initiation (0.053 mM) and of L-glutamate-pyruvate transaminase (0.068 mM) were similar, whereas that for L-alanine dehydrogenase (0.4 mM) was six to seven times higher. Since a mutant lacking L-alanine dehydrogenase activity germinated normally in L-alanine alone, it is speculated that the major pathway of L-alanine metabolism during initiation may be via transmination reaction.

Metabolism and the triggering of germination of Bacillus megaterium. Concentrations of amino acids, organic acids, adenine nucleotides and nicotinamide nucleotides during germination

“…These three acids (plus oxaloacetate, which was measured as pyruvate) were selected for analysis because they are convenient intermediates of the two halves of the tricarboxylic acid cycle and of the lower half of glycolysis. Pyruvate is also the product of alanine dehydrogenase (EC 1.4.1.1), which has often been suggested to be the site of action of L-alanine as a germinant, and a-oxoglutarate is necessary for the action of the transaminases, which have been implicated in spore germination (Prasad, 1974). Fig.…”

“…intermediates of the tricarboxylic acid cycle could the extended also not be found, and the absence of a-oxoglutarate from the dormant spore makes a role for glutamateexperiments. pyruvate transaminase (EC 2.6.1.2) in alanineted until 4min induced germination (Prasad, 1974) unlikely. No it is unlikely pyruvate could be detected (produced from alanine important in by alanine dehydrogenase), suggesting that the production of pyruvate by spores inhibited from germination by an inhibitor of pyruvate metabolism (Halvorson & Church, 1957) may be due to the presence ofthe inhibitor rather than to a germinationrelated event.…”

“…The accumulated evidence from several experimental approaches has nevertheless suggested that germinant metabolism or germinant-stimulated metabolism is the initiating signal. This evidence includes studies on the effect of electron-transport inhibitors (Dring & Gould, 1975;Yoshiaki, 1974) and the inhibition of L-alanine-induced germination by inhibitors of pyruvate metabolism (Prasad, 1974;Halvorson & Church, 1957). In addition, studies with Bacillus subtilis mutants (Wax et al, 1967;Wax & Freese, 1968;Prasad et al, 1972) strongly suggest a role for glycolysis in germination triggering.…”

Integrative analysis of proteome and transcriptome dynamics duringBacillus subtilisspore revival

“…Especially acetate formation is an energy producing step 36 that is beneficial for germination and outgrowth. It has been observed that pyruvate formed via Ald may be converted to fructose-6-phosphate via gluconeogenesis thus fuelling cellular energy generation processes 37 . Protein YoeB (IseA), an autolysis activation modulator 38,39 may serve as a controller restricting cell division ahead of time.…”

Study of inhibition of outgrowth in Bacillus cereus T by ethyl picolinate

“…Realization that the selective inhibition of specific stages during germination is the best approach to prevent this spoilage has led to the search for metabolic inhibitors. The inhibitory compounds reported to date belong to the following classes: long-chain fatty acids (3), analogues of amino acids (2,6), purines and pyrmidines (2,9), metal chelators and ions (7), and antibiotics (5).…”