ATP concentration in Escherichia coli during oxygen toxicity.

Escherichia coli, strain E-26, grown in defined salts medium with glucose as the sole carbon and energy source, contained 1.50+/-0.16-10(6) molecules of ATP/cell. ATP was extracted with HC104 and assayed with a Dupont Luminescence Biometer using the luciferin-luciferase assay. Exposure during exponential growth at 37degreesC to 4.2 atm of oxygen resulted in complete growth cessation within 5 min, and to cyclic changes in cellular ATP concentration over a 2 h period. However, significant decrease in cellular ATP concentration occurred after growth inhibition in hyperbaric oxygen; hence, lack of ATP was not the cause of growth inhibition from oxygen toxicity.