Testosterone 17beta-dehydrogenase

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.

testosterone 17-beta-dehydrogenase (NAD+)
Identifiers
EC no.	1.1.1.63
CAS no.	9028-62-0
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 / QuickGO
Search PMC articles PubMed articles NCBI proteins

testosterone 17-beta-dehydrogenase (NADP+)
Identifiers
EC no.	1.1.1.64
CAS no.	9028-63-1
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 / QuickGO
Search PMC articles PubMed articles NCBI proteins

Names

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⁺

Main article: 3alpha(17beta)-hydroxysteroid dehydrogenase (NAD+)

This variant of testosterone 17beta-dehydrogenase (EC 1.1.1.239) catalyzes the reaction

testosterone + NAD⁺ ${\displaystyle \rightleftharpoons }$ 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⁺

Main article: Testosterone 17b-dehydrogenase (NADP+)

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

testosterone + NADP⁺ ${\displaystyle \rightleftharpoons }$ 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⁺.

See also

• Testosterone glucuronide