Induction of respiratory incompetent mutants by unsaturated fatty acid depletion in [formula omitted

Abstract

Constant levels of cellular unsaturated fatty acids were obtained by growing a fatty acid desaturase mutant of Saccharomyces cerevisiae in glucose limited chemostat cultures supplemented with various concentrations of Tween 80. An increase in the frequency of cytoplasmic respiratory incompetent mutants was observed in cultures growing at low cellular levels of unsaturated fatty acids. This effect has been shown to result from an increase in the rate of mutation as the cellular unsaturated fatty acid level is decreased. The majority of induced petite mutants are ϱ° (contain no mitochondrial DNA).