A Study on Yeast Using the Photoreactivation Process to Repair the Pyrimidine Dimer Mutations

Sunlight has an indispensable importance for living things in nature [1-3]. However, the direct absorption of UV will lead to the formation of pyrimidine dimers between adjacent pyrimidines in DNA strands usually in the form of cyclobutene pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts (6-4PPs) which causes great damage [4-6]. A DNA repair system, known as photoreactivation, can effectively repair the dimers using photolyase [7-9], which has currently been found in plants, prokaryotic and eukaryotic cells [10-12]. This study was carried out to determine whether photolyase DNA repair can be observed in yeast. Several yeast Petri dishes were treated with ultraviolet radiation, different treatments were then added to them, and the colonies were counted after culturing, hence verifying that yeasts can use the photoreactivation process.