title: Isolation and analysis of ketoconazole resistant mutants of Saccharomyces 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 a 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.
mesh_terms: D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis; D004352:Drug Resistance, Microbial / Q000235:genetics; D004875:Ergosterol / Q000096:biosynthesis; D008401:Gas Chromatography-Mass Spectrometry; D005816:Genetic Complementation Test; D007654:Ketoconazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D013056:Spectrophotometry, Ultraviolet
chemical_list: D003577:Cytochrome P-450 Enzyme System; D007654:Ketoconazole; D004875:Ergosterol