Inhibition of yeast cytochrome P-450 by ammonium metavanadate.
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.
Del Carratore
R
R
Istituto di Mutagenesi e Differenziamento, CNR, Pisa, Italy.
Morichetti
E
E
Galli
A
A
Galeotti
C
C
Bronzetti
G
G
D015660:7-Alkoxycoumarin O-Dealkylase / Q000037:antagonists & inhibitors; D065607:Cytochrome P-450 Enzyme Inhibitors; D004591:Electrophoresis, Polyacrylamide Gel; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D008861:Microsomes / Q000201:enzymology; D010105:Oxygenases / Q000037:antagonists & inhibitors; D012331:RNA, Fungal / Q000187:drug effects; D012333:RNA, Messenger / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects*; D014638:Vanadates / Q000633:toxicity*
D065607:Cytochrome P-450 Enzyme Inhibitors; D012331:RNA, Fungal; D012333:RNA, Messenger; D014638:Vanadates; D010105:Oxygenases; D015660:7-Alkoxycoumarin O-Dealkylase