ATP content and adenylate energy charge ofBacillus stearothermophilus during growth

The ATP content and the adenylate energy charge of the thermophileBacillus stearothermophilus were determined during growth.Bacillus subtilis was used for comparison to determine whether there were differences in the ATP content and adenylate energy charge between a mesophile and a thermophile. Both the ATP content and the adenylate energy charge were lower in the thermophile than in the mesophile. These lower values may reflect a decreased activation energy required for the metabolic coupling when growth is occurring at the higher temperatures characteristic of the thermophile.