2006 Volume 28 Issue 2 Pages 74-76
The mechanisms of the toxic effects of UVA (320-400 nm) irradiation remain unclear. The actions of monochromatic longer wavelength UVA, in particular, have been difficult to analyze because of a lack of a powerful light source; however, a UVA laser that can be used for biological studies was recently developed. In the current studies, we examined the effects of 364-nm irradiation on yeast cells using a potent UVA laser. We found that, when irradiated under aerobic conditions, yeast cells lacking Ogg1 glycosylase were more sensitive than those with Ogg1. The ability of the 364-nm light to kill the yeast cells was almost eliminated by purging with argon gas. The mutagenic effects of the UVA irradiation did not appear to be enhanced by a lack of Ogg1. These results indicate the killing of yeast cells by 364-nm UVA may be dependent on oxidation and may involve DNA lesions that can be repaired by Ogg1.
