Primary Structure of the P450 Lanosterol Demethylase Gene from<i>Saccharomyces cerevisiae</i>

Kalb, Vernon F.; Woods, Connie W.; Turi, Thomas G.; Dey, Chitta R.; Sutter, Thomas R.; Loper, John C.

doi:10.1089/dna.1987.6.529

Cited by 176 publications

(94 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…CYP51A1 is essential for aerobic growth of yeast [22], and probably in fungi generally. Studies on this protein and its inhibition are of practical and academic significance and enantiomers of the numerous drugs and pesticides are proving useful tools with which to undertake molecular modelling studies [4,23].…”

Section: Discussionmentioning

confidence: 99%

Altered P450 activity associated with direct selection for fungal azole resistance

et al. 1995

View full text Add to dashboard Cite

Azole antifungals inhibit CYP51Al-mediated sterol 14c~-demethylation and the mechanism(s) of resistance to such compounds in Ustilago maydis were examined. The inhibition of growth was correlated with the accumulation of the snbstrate, 24-methylene-24,25-dihydrolanosterol (eburicol), and depletion of ergosterol. Mutants overcoming the effect of azole antifungal treatment exhibited a unique phenotype with leaky CYP51A1 activity which was resistant to inhibition. The results demonstrate that alterations at the level of inhibitor binding to the target site can produce azole resistance. Similar changes may account for fungal azole resistance phenomena in agriculture, and also in medicine where resistance has become a problem in immunocompromised patients suffering from AIDS.

show abstract

Section: Discussionmentioning

confidence: 99%

Altered P450 activity associated with direct selection for fungal azole resistance

et al. 1995

View full text Add to dashboard Cite

show abstract

“…The highest homology noted for the predicted DIT2 gene product was 24% identity with the bovine cytochrome P-450 XVIIA1 (17et-hydroxylase/17,20 lyase; Zuber et al 1986). Identity with the rat cytochrome P-450 IIIA1 [pregnenolone 16a-carbonitrile-inducible {pcnl); Gonzalez et al 1985], rat P-450 IIIA2 [(pcn2); Gonzalez et al 1986], and human P-450 XIA1 [cholesterol side-chain cleavage (scc); Chung et al 1986] was -20%, whereas identity with the only previous known cytochrome P-450 of S. cerevisiae (P-450 LI, lanosterol 14a-demethylase; Kalb et al 1987) was only 12%.…”

Section: Dit2 Is a M E M B E R Of The C Y T O C H R O M E P-450 Supermentioning

confidence: 99%

Isolation of two developmentally regulated genes involved in spore wall maturation in Saccharomyces cerevisiae.

Briza¹,

Breitenbach²,

Ellinger³

et al. 1990

Genes Dev.

198

233

View full text Add to dashboard Cite

During sporulation of Saccharomyces cerevisiae, the four haploid nuclei generated by meiosis are encapsulated within multilayered spore walls. Taking advantage of the natural fluorescence imparted to yeast spores by the presence of a dityrosine-containing macromolecule in the spore wall, we identified and cloned two genes, termed DIT1 and DIT2, which are required for spore wall maturation. Mutation of these genes has no effect on the efficiency of spore formation or spore viability. The mutant spores, however, fail to accumulate the spore wall-specific dityrosine and lack the outermost layer of the spore wall. The absence of this cross-linked surface layer reduces the resistance of the spores to lyric enzymes, to ether, and to elevated temperature. Expression of the DIT and DIT2 genes is restricted to sporulating cells, with the DIT1 transcripts accumulating at the time of prospore enclosure and just prior to the time of dityrosine biosynthesis. Both genes act in a sporeautonomous manner implying that at least some of the activities responsible for forming the outermost layer of the spore wall reside within the developing spore rather than in the surrounding ascal cytoplasm. As the DIT2 gene product has significant homology with cytochrome P-450s, DIT2 may be responsible for catalyzing the oxidation of tyrosine residues in the formation of dityrosine.

show abstract

“…Our results show that at least two of these reactions are not catalyzed by the biosynthetic enzyme P-45014DM and imply that there exist several distinct enzymes in some yeasts or isozymes of P-45014DM capable of catalyzing these reactions. The molecular weight and amino acid composition for the benzo[a]pyrene hydroxylase have been determined (23) and are clearly distinct from the molecular weight of P-45014DM (56; our unpublished results) and the amino acid composition determined from the cDNA sequence for P-45014DM (19). This supports the presence of multiple P-450s in yeasts; however, it is not known if the benzo[a]pyrene hydroxylase will metabolize lanosterol.…”

Section: Resultsmentioning

confidence: 53%

Induction and substrate specificity of the lanosterol 14 alpha-demethylase from Saccharomyces cerevisiae Y222

Wright

Honek

1991

J Bacteriol

View full text Add to dashboard Cite

The potential inducibility of the lanosterol 14at-demethylase (P-45014DM) from Saccharomyces cerevisiae Y222 by xenobiotics was investigated. This enzyme and NADPH-cytochrome P-450 reductase were unaffected by a number of compounds known to induce mammalian and some yeast cytochrome P-450 monooxygenases. Furthermore, dibutyryl cyclic AMP did not affect P-45014DM or P-450 reductase levels, while growth at 37°C resulted in a slight decrease. P-45014DM was found to be specific for lanosterol and did not metabolize a number of P-450 substrates including benzo[alpyrene.The lanosterol 14a-demethylase (P-45014DM) in yeasts and fungi is the target for the clinically and agriculturally important imidazole and triazole antifungal agents (5,43,55). Inhibition of this membrane-bound cytochrome P-450 monooxygenase (P-450) results in decreased biosynthesis of the major fungal sterol ergosterol and accumulation of C-14-methylated sterol precursors. Ergosterol depletion results in altered membrane permeability and decreased activity of membrane enzymes such as chitin synthetase (42), which may contribute to inhibition of fungal growth. P-45014DM from the yeasts Saccharomyces cerevisiae and Candida albicans has been purified (15, 56) and cloned (18,25).Many mammalian P-450s can be induced by a variety of compounds. In particular, these chemicals induce a specific enzyme, or group of enzymes, which catalyze distinct reactions (47, 53). There are several different classes of compounds which are known to induce mammalian P-450s; these include the phenobarbital class of compounds (12), polyaromatic hydrocarbons (e.g., 3-methylcholanthrene) (28), steroids (e.g., dexamethasone) (35), pituitary hormones (44), and ethanol (37), among others. P-450s in S. cerevisiae have been shown to catalyze a number of reactions, including lanosterol demethylation (2), A22-sterol desaturation (13), hydroxylation of benzo[a]pyrene (52), deethylation of 7-ethoxycoumarin (8), and activation of promutagens such as dimethylnitrosamine (6). Little is known about the induction of P-450 in yeasts. Ishidate and coworkers (17) We have previously noted a relationship between iron and P-450 content in S. cerevisiae Y222 (54).While it seems probable that the various reactions catalyzed by P-450s are performed by distinct enzymes, only one P-450 locus has yet been identified in S. cerevisiae (18). Because of the small quantities of P-450 in yeast and fungi compared with those in mammalian sources, extensive studies on these enzymes are hampered by the availability of P-450. In this study we have investigated the induction of P-45014DM in S. cerevisiae Y222. It is shown that this enzyme is the only P-450 produced by this organism and that it does not metabolize a number of mammalian P-450 substrates. MATERIALS AND METHODSMaterials. trans-1,4-Bis(2-chlorobenzylaminomethylcyclohexane dihydrochloride) (AY-9944) was a gift from WyethAyerst Research (Princeton, N.J.). Benzo[a]pyrene, 3-methylcholanthrene, dilaurylphosphatidylcholine, Tergitol 15-S-12, and lanosterol w...

show abstract

Primary Structure of the P450 Lanosterol Demethylase Gene fromSaccharomyces cerevisiae

Cited by 176 publications

References 51 publications

Altered P450 activity associated with direct selection for fungal azole resistance

Altered P450 activity associated with direct selection for fungal azole resistance

Isolation of two developmentally regulated genes involved in spore wall maturation in Saccharomyces cerevisiae.

Induction and substrate specificity of the lanosterol 14 alpha-demethylase from Saccharomyces cerevisiae Y222

Contact Info

Product

Resources

About