Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Steroid 17-alpha-hydroxylase/17,20 lyase; A cytochrome P450 monooxygenase involved in corticoid and androgen biosynthesis. Catalyzes 17-alpha hydroxylation of C21 steroids, which is common for both pathways. A second oxidative step, required only for androgen synthesis, involves an acyl-carbon cleavage. The 17-alpha hydroxy intermediates, as part of adrenal glucocorticoids biosynthesis pathway, are precursors of cortisol (Probable). Hydroxylates steroid hormones, pregnenolone and progesterone to form 17-alpha hydroxy metabolites, followed by the cleavage of the C17-C20 bond to form C1 [...]

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Aromatase; A cytochrome P450 monooxygenase that catalyzes the conversion of C19 androgens, androst-4-ene-3,17-dione (androstenedione) and testosterone to the C18 estrogens, estrone and estradiol, respectively. Catalyzes three successive oxidations of C19 androgens: two conventional oxidations at C19 yielding 19-hydroxy and 19-oxo/19-aldehyde derivatives, followed by a third oxidative aromatization step that involves C1-beta hydrogen abstraction combined with cleavage of the C10-C19 bond to yield a phenolic A ring and formic acid. Alternatively, the third oxidative reaction yields a 19- [...]

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Steroid 21-hydroxylase; Specifically catalyzes the 21-hydroxylation of steroids. Required for the adrenal synthesis of mineralocorticoids and glucocorticoids.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Dehydrogenase/reductase SDR family member 11; Catalyzes the conversion of the 17-keto group of estrone, 4- and 5-androstenes and 5-alpha-androstanes into their 17-beta- hydroxyl metabolites and the conversion of the 3-keto group of 3-, 3,17- and 3,20- diketosteroids into their 3-hydroxyl metabolites. Exhibits reductive 3-beta-hydroxysteroid dehydrogenase activity toward 5-beta-androstanes, 5-beta-pregnanes, 4-pregnenes and bile acids. May also reduce endogenous and exogenous alpha-dicarbonyl compounds and xenobiotic alicyclic ketones.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Dehydrogenase/reductase SDR family member 9; 3-alpha-hydroxysteroid dehydrogenase that converts 3-alpha- tetrahydroprogesterone (allopregnanolone) to dihydroxyprogesterone and 3-alpha-androstanediol to dihydroxyprogesterone. Plays also a role in the biosynthesis of retinoic acid from retinaldehyde. Can utilize both NADH and NADPH. Belongs to the short-chain dehydrogenases/reductases (SDR) family.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Corticosteroid 11-beta-dehydrogenase isozyme 2; Catalyzes the conversion of cortisol to the inactive metabolite cortisone. Modulates intracellular glucocorticoid levels, thus protecting the nonselective mineralocorticoid receptor from occupation by glucocorticoids.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Very-long-chain 3-oxoacyl-CoA reductase; Catalyzes the second of the four reactions of the long-chain fatty acids elongation cycle. This endoplasmic reticulum-bound enzymatic process, allows the addition of two carbons to the chain of long- and very long-chain fatty acids/VLCFAs per cycle. This enzyme has a 3-ketoacyl-CoA reductase activity, reducing 3-ketoacyl-CoA to 3- hydroxyacyl-CoA, within each cycle of fatty acid elongation. Thereby, it may participate in the production of VLCFAs of different chain lengths that are involved in multiple biological processes as precursors of membra [...]

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 1; A bifunctional enzyme responsible for the oxidation and isomerization of 3beta-hydroxy-Delta(5)-steroid precursors to 3-oxo- Delta(4)-steroids, an essential step in steroid hormone biosynthesis. Specifically catalyzes the conversion of pregnenolone to progesterone, 17alpha-hydroxypregnenolone to 17alpha-hydroxyprogesterone, dehydroepiandrosterone (DHEA) to 4-androstenedione, and androstenediol to testosterone. Additionally, catalyzes the interconversion between 3beta-hydroxy and 3-oxo-5alpha-androstane steroids controlli [...]

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 2; 3-beta-HSD is a bifunctional enzyme, that catalyzes the oxidative conversion of Delta(5)-ene-3-beta-hydroxy steroid, and the oxidative conversion of ketosteroids. The 3-beta-HSD enzymatic system plays a crucial role in the biosynthesis of all classes of hormonal steroids.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Insulin A chain; Insulin decreases blood glucose concentration. It increases cell permeability to monosaccharides, amino acids and fatty acids. It accelerates glycolysis, the pentose phosphate cycle, and glycogen synthesis in liver.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Steroidogenic acute regulatory protein, mitochondrial; Plays a key role in steroid hormone synthesis by enhancing the metabolism of cholesterol into pregnenolone. Mediates the transfer of cholesterol from the outer mitochondrial membrane to the inner mitochondrial membrane where it is cleaved to pregnenolone.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Steryl-sulfatase; Catalyzes the conversion of sulfated steroid precursors, such as dehydroepiandrosterone sulfate (DHEA-S) and estrone sulfate to the free steroid.

Cholesterol side-chain cleavage enzyme, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the side-chain hydroxylation and cleavage of cholesterol to pregnenolone, the precursor of most steroid hormones. Catalyzes three sequential oxidation reactions of cholesterol, namely the hydroxylation at C22 followed with the hydroxylation at C20 to yield 20R,22R- hydroxycholesterol that is further cleaved between C20 and C22 to yield the C21-steroid pregnenolone and 4-methylpentanal. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the se [...]

Translocator protein; Can bind protoporphyrin IX and may play a role in the transport of porphyrins and heme (By similarity). Promotes the transport of cholesterol across mitochondrial membranes and may play a role in lipid metabolism , but its precise physiological role is controversial. It is apparently not required for steroid hormone biosynthesis. Was initially identified as peripheral- type benzodiazepine receptor; can also bind isoquinoline carboxamides ; Belongs to the TspO/BZRP family.

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

Steroid 17-alpha-hydroxylase/17,20 lyase; A cytochrome P450 monooxygenase involved in corticoid and androgen biosynthesis. Catalyzes 17-alpha hydroxylation of C21 steroids, which is common for both pathways. A second oxidative step, required only for androgen synthesis, involves an acyl-carbon cleavage. The 17-alpha hydroxy intermediates, as part of adrenal glucocorticoids biosynthesis pathway, are precursors of cortisol (Probable). Hydroxylates steroid hormones, pregnenolone and progesterone to form 17-alpha hydroxy metabolites, followed by the cleavage of the C17-C20 bond to form C1 [...]

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

Aromatase; A cytochrome P450 monooxygenase that catalyzes the conversion of C19 androgens, androst-4-ene-3,17-dione (androstenedione) and testosterone to the C18 estrogens, estrone and estradiol, respectively. Catalyzes three successive oxidations of C19 androgens: two conventional oxidations at C19 yielding 19-hydroxy and 19-oxo/19-aldehyde derivatives, followed by a third oxidative aromatization step that involves C1-beta hydrogen abstraction combined with cleavage of the C10-C19 bond to yield a phenolic A ring and formic acid. Alternatively, the third oxidative reaction yields a 19- [...]

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

Steroid 21-hydroxylase; Specifically catalyzes the 21-hydroxylation of steroids. Required for the adrenal synthesis of mineralocorticoids and glucocorticoids.

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

Dehydrogenase/reductase SDR family member 11; Catalyzes the conversion of the 17-keto group of estrone, 4- and 5-androstenes and 5-alpha-androstanes into their 17-beta- hydroxyl metabolites and the conversion of the 3-keto group of 3-, 3,17- and 3,20- diketosteroids into their 3-hydroxyl metabolites. Exhibits reductive 3-beta-hydroxysteroid dehydrogenase activity toward 5-beta-androstanes, 5-beta-pregnanes, 4-pregnenes and bile acids. May also reduce endogenous and exogenous alpha-dicarbonyl compounds and xenobiotic alicyclic ketones.

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

Corticosteroid 11-beta-dehydrogenase isozyme 2; Catalyzes the conversion of cortisol to the inactive metabolite cortisone. Modulates intracellular glucocorticoid levels, thus protecting the nonselective mineralocorticoid receptor from occupation by glucocorticoids.

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 1; A bifunctional enzyme responsible for the oxidation and isomerization of 3beta-hydroxy-Delta(5)-steroid precursors to 3-oxo- Delta(4)-steroids, an essential step in steroid hormone biosynthesis. Specifically catalyzes the conversion of pregnenolone to progesterone, 17alpha-hydroxypregnenolone to 17alpha-hydroxyprogesterone, dehydroepiandrosterone (DHEA) to 4-androstenedione, and androstenediol to testosterone. Additionally, catalyzes the interconversion between 3beta-hydroxy and 3-oxo-5alpha-androstane steroids controlli [...]

Cytochrome P450 11B2, mitochondrial; A cytochrome P450 monooxygenase that catalyzes the biosynthesis of adrenal mineralocorticoid aldosterone. Catalyzes three sequential oxidative reactions of 11-deoxycorticosterone/21- hydroxyprogesterone, namely 11-beta hydroxylation followed with two successive oxidations at C18 to yield 18-hydroxy and then 18-aldehyde derivatives, resulting in the formation of aldosterone. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule. Two electrons are provided by NADPH via a two-pro [...]

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 2; 3-beta-HSD is a bifunctional enzyme, that catalyzes the oxidative conversion of Delta(5)-ene-3-beta-hydroxy steroid, and the oxidative conversion of ketosteroids. The 3-beta-HSD enzymatic system plays a crucial role in the biosynthesis of all classes of hormonal steroids.