| Ontology | CARD's Antibiotic Resistance Ontology |
| Accession | ARO:3009245 |
| Definition | Erg3 is a distinct member of the P450 class of enzymes that encodes C-5 sterol desaturase that functions in the late ergosterol biosynthesis pathway in fungi. It catalyzes the introduction of a C-5,6 double bond into episterol and is localized to the ER membrane. Azole-mediated inhibition of Erg11 causes accumulation of toxic 14-alpha-methylated sterol intermediates and Erg3 acts on these intermediates to produce the species that are toxic to the cell. Loss-of-function mutations in ERG3 therefore confer azole tolerance by preventing the conversion of these intermediates into their toxic form, allowing the cell to survive drug exposure despite compromised ergosterol synthesis. There may be a fitness cost due to simultaneous compromises to membrane composition. |
| AMR Gene Family | azole resistant fungal C-5 sterol desaturase |
| Drug Class | azole antibiotic, triazole antifungal |
| Resistance Mechanism | antibiotic target alteration |
| Classification | 13 ontology terms | Show + process or component of antibiotic biology or chemistry + mechanism of antibiotic resistance + antibiotic target alteration [Resistance Mechanism] + mutation conferring antibiotic resistance + determinant of antibiotic resistance + antibiotic molecule + antibiotic resistance gene variant or mutant + antifungal-resistant cytochrome P450 enzyme + azole antibiotic [Drug Class] + antibiotic target + antifungal resistant fungal C-5 sterol desaturase + fungal ergosterol synthesis pathway enzyme + triazole antifungal [Drug Class] |
| Parent Term(s) | 3 ontology terms | Show + confers_resistance_to_antibiotic voriconazole [Antibiotic] + azole resistant fungal C-5 sterol desaturase [AMR Gene Family] + derives_from antifungal susceptible ERG3 C-5 sterol desaturase |
| Curator | Description | Most Recent Edit |
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