Testosterone 17beta-dehydrogenase

testosterone 17-beta-dehydrogenase (NAD+)
Identifiers
EC number	1.1.1.63
CAS number	Template:CAS
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles NCBI proteins

testosterone 17-beta-dehydrogenase (NADP+)
Identifiers
EC number	1.1.1.64
CAS number	Template:CAS
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles NCBI proteins

In enzymology, a testosterone 17beta-dehydrogenase is an enzyme that catalyzes the chemical reaction between testosterone and androst-4-ene-3,17-dione.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is 17beta-hydroxysteroid:NAD⁺ 17-oxidoreductase. Other names in common use include 17-ketoreductase, and 17beta-HSD. This enzyme participates in androgen and estrogen metabolism.

Variants

There are two variants of the enzyme, one that uses NAD⁺ as a substrate, and one that uses NADP⁺ as acceptor.

NAD⁺

This variant of testosterone 17beta-dehydrogenase (EC 1.1.1.63) catalyzes the reaction

testosterone + NAD⁺ $\rightleftharpoons$ androst-4-ene-3,17-dione + NADH + H⁺

Thus, the two substrates of this enzyme are testosterone and NAD⁺, whereas its 3 products are androst-4-ene-3,17-dione, NADH, and H⁺.

NADP⁺

This variant of testosterone 17beta-dehydrogenase (EC 1.1.1.64) catalyzes the reaction

testosterone + NADP⁺ $\rightleftharpoons$ androst-4-ene-3,17-dione + NADPH + H⁺

Thus, the two substrates of this enzyme are testosterone and NADP⁺, whereas its 3 products are androst-4-ene-3,17-dione, NADPH, and H⁺.