Long-wave (320-400 nm) UV-induced oxygen superoxide anion radical (O2-) formation was found in yeast cells. This radical plays an important part in initiation of photodestruction reactions in DNA which serves as a main target of UV irradiation in yeast. The observed cell photoinactivation spectrum at the wavelengths 320-400 nm suggests that NADH can serve as an endogenous sensitizer of O2- formation.
Candida DNA, Fungal