Mechanism of the third oxidative step in the conversion of androgens to estrogens by cytochrome P450 19A1 steroid aromatase.
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ABSTRACT:
SUBMITTER: Yoshimoto FK
PROVIDER: S-EPMC4210144 | biostudies-literature | 2014 Oct
REPOSITORIES: biostudies-literature
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Mechanism of the third oxidative step in the conversion of androgens to estrogens by cytochrome P450 19A1 steroid aromatase.
Yoshimoto Francis K FK Guengerich F Peter FP
Journal of the American Chemical Society 20141010 42
Aromatase is the cytochrome P450 enzyme that cleaves the C10-C19 carbon-carbon bond of androgens to form estrogens, in a three-step process. Compound I (FeO(3+)) and ferric peroxide (FeO2(-)) have both been proposed in the literature as the active iron species in the third step, yielding an estrogen and formic acid. Incubation of purified aromatase with its 19-deutero-19-oxo androgen substrate was performed in the presence of (18)O2, and the products were derivatized using a novel diazo reagent. ...[more]
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