Near-ultraviolet radiation and hydrogen peroxide modulate intracellular levels of potassium and thiols inEscherichia coli

Treatment of aerobicEscherichia coli K 12 with nonlethal doses of near-ultraviolet (NUV) and H₂O₂ resulted in the same physiological response. In response to stress caused by these agents, an inhibition of growth, a decrease in intracellular K⁺ pool, and an increase in intracellular levels of protein and nonprotein thiols were observed. A possible role for glutathione in the process of adaptation ofE. coli culture to growth under the conditions of oxidative stress is discussed.