ABSTRACT
Susceptibility of strain S288c of Saccharomyces cerevisiae to fluconazole was assayed in the presence and absence of KCl. Addition of 150 mM KCl renders the strain more sensitive to the antifungal agent. The effect is caused by the K(+) ion rather than the anion or the osmolarity of the medium. The increase in sensitivity does not modify the values of intracellular and extracellular pH established in the presence of KCl.
Subject(s)
Antifungal Agents/pharmacology , Fluconazole/pharmacology , Potassium Chloride/pharmacology , Saccharomyces cerevisiae/drug effects , Colony Count, Microbial , Drug Interactions , Drug Resistance, Microbial , Hydrogen-Ion Concentration , Microbial Sensitivity TestsABSTRACT
Severe mycotic infections are a source of concern in immunocompromised patients or in those who receive chemotherapy for hematological malignant diseases. One of the causes is referred to the appearance of antimycotic resistant microorganisms. Fluconazole is one of the antimycotic used for invasive mycoses treatment. Therefore it is necessary to evaluate the factors that originate this resistance. In the present report the yeast Saccharomyces cerevisiae S288c was used as a model system. In resistant strains the accumulation of the lipophilic cation Rhodamine 6G, L-leucine uptake and growth inhibition by crystal violet dye were determined. The results presented herein demonstrate the correlation between the membrane potential and the resistance to fluconazole presented by S. cerevisiae strain S288c.
Subject(s)
Antifungal Agents/pharmacology , Drug Resistance, Microbial , Fluconazole/pharmacology , Membrane Potentials/drug effects , Rhodamines/metabolism , Saccharomyces cerevisiae/metabolism , Antifungal Agents/metabolism , Culture Media/pharmacology , Fluconazole/metabolism , Gentian Violet/metabolism , Gentian Violet/pharmacology , Leucine/metabolism , Membrane Lipids/metabolism , Proline/pharmacology , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/growth & development , Sterols/metabolismABSTRACT
Severe mycotic infections are a source of concern in immunocompromised patients or in those who receive chemotherapy for hematological malignant diseases. One of the causes is referred to the appearance of antimycotic resistant microorganisms. Fluconazole is one of the antimycotic used for invasive mycoses treatment. Therefore it is necessary to evaluate the factors that originate this resistance. In the present report the yeast Saccharomyces cerevisiae S288c was used as a model system. In resistant strains the accumulation of the lipophilic cation Rhodamine 6G, L-leucine uptake and growth inhibition by crystal violet dye were determined. The results presented herein demonstrate the correlation between the membrane potential and the resistance to fluconazole presented by S. cerevisiae strain S288c.(AU)
Subject(s)
Comparative Study , Antifungal Agents/pharmacology , Drug Resistance, Microbial , Fluconazole/pharmacology , Membrane Potentials/drug effects , Rhodamines/metabolism , Saccharomyces cerevisiae/metabolism , Antifungal Agents/metabolism , Culture Media/pharmacology , Fluconazole/metabolism , Gentian Violet/metabolism , Gentian Violet/pharmacology , Leucine/metabolism , Membrane Lipids/metabolism , Proline/pharmacology , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/growth & development , Sterols/metabolismABSTRACT
Severe mycotic infections are a source of concern in immunocompromised patients or in those who receive chemotherapy for hematological malignant diseases. One of the causes is referred to the appearance of antimycotic resistant microorganisms. Fluconazole is one of the antimycotic used for invasive mycoses treatment. Therefore it is necessary to evaluate the factors that originate this resistance. In the present report the yeast Saccharomyces cerevisiae S288c was used as a model system. In resistant strains the accumulation of the lipophilic cation Rhodamine 6G, L-leucine uptake and growth inhibition by crystal violet dye were determined. The results presented herein demonstrate the correlation between the membrane potential and the resistance to fluconazole presented by S. cerevisiae strain S288c.
Subject(s)
Antifungal Agents/pharmacology , Fluconazole , Membrane Potentials , Drug Resistance, Microbial , Rhodamines , Saccharomyces cerevisiae , Antifungal Agents/metabolism , Culture Media , Sterols/metabolism , Fluconazole , Gentian Violet , Leucine , Membrane Lipids/metabolism , Proline , Saccharomyces cerevisiaeABSTRACT
Severe mycotic infections are a source of concern in immunocompromised patients or in those who receive chemotherapy for hematological malignant diseases. One of the causes is referred to the appearance of antimycotic resistant microorganisms. Fluconazole is one of the antimycotic used for invasive mycoses treatment. Therefore it is necessary to evaluate the factors that originate this resistance. In the present report the yeast Saccharomyces cerevisiae S288c was used as a model system. In resistant strains the accumulation of the lipophilic cation Rhodamine 6G, L-leucine uptake and growth inhibition by crystal violet dye were determined. The results presented herein demonstrate the correlation between the membrane potential and the resistance to fluconazole presented by S. cerevisiae strain S288c.
ABSTRACT
Fluconazole inhibition of Saccharomyces cerevisiae S288c growth was evaluated in media containing ammonia, L-proline or L-leucine as a nitrogen source. Growth inhibition by fluconazole was maximum when L-proline was used as a nitrogen source, while rhodamine 6G accumulation and fluconazole resistance were the highest when ammonia was the sole nitrogen source.
