Ligand pregnenolone

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.

Basic Ligand Information

Molecular Structure
Picture of pregnenolone (click for magnification)
Molecular Formula
BRENDA Name
InChIKey
C21H32O2
pregnenolone
ORNBQBCIOKFOEO-QGVNFLHTSA-N
Synonyms:
(3beta)-3-hydroxypregn-5-en-20-one, 3beta-hydroxy-5-pregnen-20-one, 3beta-hydroxypregn-5-en-20-one, 5-pregnen-3beta-ol-20-one, DELTA5-pregnen-3beta-ol-20-one, pregn-5-en-3beta-ol-20-one


Show all pahtways known for Show all BRENDA pathways known for pregnenolone

Roles as Enzyme Ligand

In Vivo Substrate in Enzyme-catalyzed Reactions (17 results)

EC NUMBER
PROVEN IN VIVO REACTION
REACTION DIAGRAM
LITERATURE
ENZYME 3D STRUCTURE

In Vivo Product in Enzyme-catalyzed Reactions (5 results)

EC NUMBER
PROVEN IN VIVO REACTION
REACTION DIAGRAM
LITERATURE
ENZYME 3D STRUCTURE

Substrate in Enzyme-catalyzed Reactions (48 results)

EC NUMBER
REACTION
REACTION DIAGRAM
LITERATURE
ENZYME 3D STRUCTURE
pregnenolone + NADH + H+ = progesterone + NAD+
show the reaction diagram
-
pregnenolone + NADP+ = ?
show the reaction diagram
-
pregnenolone + NADPH = 3beta,20beta-Dihydroxypregn-5-ene + NADP+
show the reaction diagram
-
Pregnenolone + NADPH + O2 = ?
show the reaction diagram
-
DELTA5-pregnen-3beta-ol-20-one + NADH + O2 = deoxycorticosterone + NAD+ + H2O
show the reaction diagram
-
pregnenolone + 2 reduced ferredoxin [iron-sulfur] cluster + H+ + O2 = ?
show the reaction diagram
-
pregnenolone + reduced adrenodoxin + O2 = 7beta-hydroxy-pregnenolone + oxidized adrenodoxin + H2O
show the reaction diagram
-
pregn-5-en-3beta-ol-20-one + UDP-glucose = UDP + pregn-5-en-3beta-ol-20-one 3-O-beta-D-glucoside
show the reaction diagram
-
3'-phosphoadenylylsulfate + pregnenolone = adenosine 3',5'-bisphosphate + pregnenolone 3-sulfate
show the reaction diagram
-
pregnenolone = progesterone
show the reaction diagram
-

Product in Enzyme-catalyzed Reactions (17 results)

EC NUMBER
REACTION
REACTION DIAGRAM
LITERATURE
ENZYME 3D STRUCTURE
3beta,20alpha-dihydroxypregn-5-ene + NADP+ = 3beta-hydroxypregn-5-en-20-one + NADPH
show the reaction diagram
-
-
5-pregnen-3,20-dione + O2 = pregnenolone + H2O2
show the reaction diagram
-
-

Inhibitor in Enzyme-catalyzed Reactions (10 results)

EC NUMBER
COMMENTARY
LITERATURE
ENZYME 3D STRUCTURE
competitive inhibition
-
and other C21-20-ketosteroids which are the substrates for oxygenative esterification of the enzyme, strongly inhibit lactonization of androstenedione
-
substrate inhibition
-
1 mM, 10% inhibition
-

3D Structure of Enzyme-Ligand-Complex (PDB) (2 results)

EC NUMBER
ENZYME 3D STRUCTURE

Enzyme Kinetic Parameters

kcat Value (Turnover Number) (31 results)

EC NUMBER
TURNOVER NUMBER [1/S]
TURNOVER NUMBER MAXIMUM [1/S]
COMMENTARY
LITERATURE
0.0047
-
for the cytosolic enzyme

KM Value (78 results)

EC NUMBER
KM VALUE [MM]
KM VALUE MAXIMUM [MM]
COMMENTARY
LITERATURE
0.004
-
-
0.0012
-
pH 7.4, 37°C, with cholesterol (0.32 mM). Without cholesterol, the Km for pregnenolone is too high to be measurable

Ki Value (1 result)

EC NUMBER
KI VALUE [MM]
KI VALUE MAXIMUM [MM]
COMMENTARY
LITERATURE
0.0008
-
competitive substrate with progesterone

IC50 Value (5 results)

EC NUMBER
IC50 VALUE
IC50 VALUE MAXIMUM
COMMENTARY
LITERATURE
0.1
-
value above 0.1 mM

References & Links

Links to other databases for pregnenolone

ChEBI
PubChem
-
PubChem