DNA Damage Kills Bacterial Spores and Cells Exposed to 222-Nanometer UV Radiation

Abstract

Spores of a variety of bacteria are resistant to common decontamination agents, and many of them are major causes of food spoilage and some serious human diseases, including anthrax caused by spores of Bacillus anthracis . Consequently, there is an ongoing need for efficient methods for spore eradication, in particular methods that have minimal deleterious effects on people or the environment. UV radiation at 254 nm (UV 254 ) is sporicidal and commonly used for surface decontamination but can cause deleterious effects in humans. Recent work, however, suggests that 222-nm UV (UV 222 ) may be less harmful to people than UV 254 yet may still kill bacteria and at lower fluences than UV 254 . The present work has identified the damage by UV 222 that leads to the killing of growing cells and spores of some bacteria, many of which are human pathogens, and UV 222 also inactivates a herpesvirus.