Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Nuclear Biology & Nuclear Chemistry Aproaches - Heme-Dependant Nuclear Chemistry - Non-Elaborate Posts - Post 2

 

 At the atomic scale, the ERG11 enzyme’s catalytic core is organized around a heme b moiety, coordinated by a conserved cysteine residue (Cys437) as the fifth ligand to the central Fe(III) ion. This configuration establishes an axial thiolate–iron bond, endowing the P450 heme with extraordinary redox potential and spectral properties. During lanosterol demethylation, molecular oxygen binds to the ferrous heme, forming transient iron–oxygen intermediates — ferric–peroxo and compound I species — capable of precise C–H bond activation. These transformations are not purely local events but are influenced by the redox milieu maintained within the nucleus. Any perturbation in nuclear NADPH flux or oxygen tension directly alters the spin state equilibrium of the heme iron, modulating the electron flow through the enzyme and, consequently, transcriptional feedback loops that regulate ERG11 expression itself.

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Fungi - Candida auris - Non-Elaborate Posts - Post 2

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