Isolation and analysis of ketoconazole resistant mutants ofSaccharomyces cerevisiae

Abstract

Nine mutants of Saccharomyces cerevisiae which are resistant to ketoconazole, have been isolated and characterized. In each case the mutation is nuclear in origin and allelic to previously described mutation, erg3, which gives rise to a block in the .DELTA.5-6 desaturation step of ergosterol biosynthesis. The significance of this second site mutation to the point of inhibitory action of ketoconazole, that is the P-450-mediated C-14 demethylation of lanosterol, is discussed.