Employing spores of
Bacillus subtilis (Marburg strain), the role of L-alanine in the germination was examined. Spores of this organism can germinate in the presence of L-alanine or L-asparagine in a chemically defined medium but can outgrow only when L-glutamate is present in addition to either one of these amino acids.
When the spores were grown in the alanine medium, in which only germination was induced, no net increase in nucleic acids was observed, whereas in the alanine-glutamate medium, in which germination and outgrowth occurred, a stepwise increase in RNA was demonstrated showing an appreciable lag during the germination period.
When the spores were fed with L-alanine-
14C, a slight but definite uptake of the tracer into spores was noticed during germination. This was confirmed by cell-fractionation experiments. A definite incorporation of L-alanine-
14C into the RNA fraction during early germination was clearly demonstrated. The finding that the labeling of RNA with the tracer amino acid in the absence of net increase in RNA during germination is discussed as compared with similar observations in germinating
Aspergillus conidia.
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