Respiration deficient mutants of Schizosaccharomyces Pombe I

Summary By use of N-methyl-N-nitro-N-nitrosoguanidin (NG) respiration deficient (RD) mutants were induced. They could be selected by replica-plating on glycerol medium. RD mutants were also induced by UV irradiation, enriched by use of 2,3,5-triphenyltetrazolium chloride (TTC) and tested for their inability to grow on glycerol medium. The RD mutants were characterized enzymatically for their decrease or loss in cytochrome c oxidase activity and in succinate- cytochrome c reductase activity. These assays allowed the localization of the mutational blocks in complexes II, III and IV of the respiratory chain. Tetrad analysis and random spore analysis demonstrated that all mutants contained chromosomal defects.