Hyper-UV-sensitive yeast I: Isolation and properties of two such mutants

Summary By using the UV-sensitive yeast mutant uvs-1 (Nakai and Matsumoto, 1967) as starting material, a series of hypersensitive strains have been isolated. Two of these strains are described here. In addition to being hyper-UV-sensitive, they are also sensitive to gamma radiation and one is sensitive to visible light; a characteristic which was first observed as an apparent failure to photoreactivate. Both strains are cytoplasmic petites. The value of this method of isolating strains which have progressively lost their dispensible repair functions is discussed.