Abstract
The effect of methanol on the induction of cytoplasmic respiration-deficient (RD) mutants of Saccharomyces cerevisiae by acriflavine (AF) was investigated. After 24 h incubation, AF at above 0.5μg/ml induced approximately 100% RD mutants in surviving cells. Methanol prevented the RD mutation by AF at concentrations less than 1.5μg/ml. The RD mutation by 0.15μg/ml AF was completely repressed by the addition of 4.0% methanol to the culture fluid. The induction frequency of RD mutants by 0.5μg/ml AF was reduced from 97 to 15% by the addition of 8.0% methanol. The AF uptake by the yeast cells was decreased in the presence of methanol. However, this methanol-induced repression in the RD mutation could not be explained simply in terms of the decrease of AF content in the yeast cells.
