Related Experiment Videos
Inhibition of yeast cytochrome P-450 by ammonium metavanadate
R Del Carratore1, E Morichetti, A Galli
1Istituto di Mutagenesi e Differenziamento, CNR, Pisa, Italy.
Abstract:
Incubation of diploid D7 strain cells of Saccharomyces cerevisiae (grown in 20% glucose) in the presence of ammonium metavanadate (AMV) led to a decrease in the cytochrome P-450-dependent monooxygenase system (cytochrome P-450 level and 7-ethoxycoumarin O-deethylase). The electrophoretic analysis of microsomal fractions of yeast cells treated with metavanadate revealed a decrease in the intensity of the bands corresponding to a M(r) in the range of 51,000-58,000 Da compared with those observed in controls, i.e., cells grown in 20% glucose. Analysis of the cytochrome P-450 transcript showed that AMV treatment reduced the mRNA level. Our results suggest that AMV inhibits the yeast cytochrome P-450 system by acting at both the pre- and post-transcriptional levels.
Insights
Ammonium metavanadate (AMV) inhibits the cytochrome P-450 system in yeast cells. This compound reduces both the protein and mRNA levels of cytochrome P-450, affecting its function.
Area of Science:
- Biochemistry
- Yeast Genetics
- Enzymology
Background:
- Cytochrome P-450 enzymes are crucial for cellular metabolism and detoxification.
- Saccharomyces cerevisiae is a widely used model organism in biological research.
- Understanding inhibitors of these systems is important for various applications.
Purpose of the Study:
- To investigate the effect of ammonium metavanadate (AMV) on the cytochrome P-450-dependent monooxygenase system in Saccharomyces cerevisiae.
- To determine the mechanisms by which AMV affects cytochrome P-450 levels and activity.
Main Methods:
- Yeast cells (Saccharomyces cerevisiae, D7 strain) were incubated with ammonium metavanadate.
- Enzyme activity assays (7-ethoxycoumarin O-deethylase) were performed.
- Microsomal fractions were analyzed using electrophoresis.
- Cytochrome P-450 transcript levels were analyzed.
Main Results:
- AMV treatment led to a significant decrease in cytochrome P-450 levels and 7-ethoxycoumarin O-deethylase activity.
- Electrophoretic analysis showed reduced protein bands in the 51,000-58,000 Da range in AMV-treated cells.
- AMV significantly reduced the mRNA levels of cytochrome P-450.
Conclusions:
- Ammonium metavanadate inhibits the yeast cytochrome P-450 system.
- The inhibition occurs at both pre-transcriptional (mRNA level) and post-transcriptional (protein level) stages.
- AMV serves as a valuable tool for studying yeast cytochrome P-450 regulation.