Activating Compound | Comment | Organism | Structure |
---|---|---|---|
cytochrome b5 | expression of cytochrome b5 in the zona reticularis, at the onset of adrenarche, increases along with the acyl-carbon bond cleavage activity of CYP17, cytochrome plays a regulatory role for CYP17 activity | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
R347A | site-directed mutagenesis, the mutant shows abolished activation by cytochrome b5 for the hydroxylase activity and overall highly reduced lyase activityindependently of cytochrome b5 | Homo sapiens |
R347H | site-directed mutagenesis, the mutant shows abolished activation by cytochrome b5 for the hydroxylase activity and overall highly reduced lyase activityindependently of cytochrome b5 | Homo sapiens |
R358A | site-directed mutagenesis, the mutant shows abolished activation by cytochrome b5 for the hydroxylase activity and overall highly reduced lyase activityindependently of cytochrome b5 | Homo sapiens |
R358Q | site-directed mutagenesis, the mutant shows abolished activation by cytochrome b5 for the hydroxylase activity and overall highly reduced lyase activityindependently of cytochrome b5 | Homo sapiens |
R449A | site-directed mutagenesis, the mutant shows abolished activation by cytochrome b5 for the hydroxylase activity and overall highly reduced lyase activityindependently of cytochrome b5 | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
19-azido-androstenedione | - |
Homo sapiens | |
19-thiomethyl-androstenedione | - |
Homo sapiens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | Homo sapiens | cytochrome P-450 17alpha-hydroxylase-17,20-lyase, CYP17, is a multifunctional enzyme. CYP17 catalyzes at the same active site not only the hydroxylation process but also an acyl-carbon bond cleavage reaction which involves the nucleophilic attack of the ferric-peroxyanion, Fe(III)-O-O-, on the acyl-carbon to furnish a tetrahedral intermediate which fragments, leading to acyl-carbon cleavage | ? | - |
? | |
pregnenolone + AH2 + O2 | Homo sapiens | - |
17alpha-hydroxypregnenolone + A + H2O | - |
? | |
progesterone + AH2 + O2 | Homo sapiens | - |
17alpha-hydroxyprogesterone + A + H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
zona reticularis | a adrenal cortex tissue layer that excretes androgens | Homo sapiens | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | cytochrome P-450 17alpha-hydroxylase-17,20-lyase, CYP17, is a multifunctional enzyme. CYP17 catalyzes at the same active site not only the hydroxylation process but also an acyl-carbon bond cleavage reaction which involves the nucleophilic attack of the ferric-peroxyanion, Fe(III)-O-O-, on the acyl-carbon to furnish a tetrahedral intermediate which fragments, leading to acyl-carbon cleavage | Homo sapiens | ? | - |
? | |
additional information | for the formation of the 16,17-ene steroid, the Fe(III)-O-O- species is trapped by the progestogen, prior to hydroxylation, and the resulting peroxy adduct decomposes to generate a C-17 radical, which is neutralized by a disproportionation reaction involving the loss of C-16-hydrogen atom, mechanism of the acyl-carbon bond cleavage reactions catalysed by CYP17, pathways for the formation of three cleavage products from peroxy adducts, overview | Homo sapiens | ? | - |
? | |
pregnenolone + AH2 + O2 | - |
Homo sapiens | 17alpha-hydroxypregnenolone + A + H2O | - |
? | |
progesterone + AH2 + O2 | - |
Homo sapiens | 17alpha-hydroxyprogesterone + A + H2O | - |
? |
Synonyms | Comment | Organism |
---|---|---|
17alpha-hydroxylase-17,20-lyase | - |
Homo sapiens |
CYP17 | - |
Homo sapiens |
General Information | Comment | Organism |
---|---|---|
additional information | in the case of CYP17 the attack of Fe(III)-O-O(-) on the target carbon is promoted by cytochrome b5, which acts as a conformational regulator of CYP17. It is this regulation of CYP17 that provides a safety mechanism which ensures that during corticoid biosynthesis, which involves 17alpha-hydroxylation by CYP17, androgen formation is avoided | Homo sapiens |