Adenosine and Spore Germination; Phase-contrast Studies

Abstract

SUMMARY: Phase-contrast microscopy enables germination to be studied in the spores of Bacillus cereus and B. subtilis a few minutes after the addition of adenosine; by this means adenosine can be identified in minute concentrations. Adenosine in high concentrations is, however, inhibitory to vegetative growth. Adenosine appears to act as an indicator of conditions suitable for vegetative existence, and induces, almost instantaneously, profound physical changes in spores. The analogy with hatching of eel-worm and amoebic cysts, also susceptible to specific excitants, is stressed.