Specific Response of Bacterial Cells to the Action of β-Ionone

The biological activity and mechanisms of action of the unsaturated ketone β-ionone, a volatile compound of serious interest for biotechnology, medicine, and agriculture, have been studied. Using specific lux-biosensors based on Escherichia coli MG1655, we found that β-ionone causes oxidative stress in E. coli cells by inducing expression from the PkatG and Pdps promoters, but not from PsoxS promoter. The effects of β-ionone on the induction of heat shock (expression from PibpA and PgrpE promoters) in E. coli cells were significantly weaker as well as its ability to cause DNA damage (expression from PcolD and PdinI promoters, SOS response). β-Ionone did not cause oxidative stress in the cells of the gram-positive bacterium Bacillus subtilis.