World Library  
Flag as Inappropriate
Email this Article

3β-hydroxysteroid Dehydrogenase

Article Id: WHEBN0022171961
Reproduction Date:

Title: 3β-hydroxysteroid Dehydrogenase  
Author: World Heritage Encyclopedia
Language: English
Subject: Dihydrotestosterone, Congenital adrenal hyperplasia due to 3 beta-hydroxysteroid dehydrogenase deficiency, Trilostane, Epiandrosterone
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

3β-hydroxysteroid Dehydrogenase

3β-hydroxysteroid dehydrogenase/Δ-5-4 isomerase
Identifiers
EC number CAS number IntEnz BRENDA ExPASy KEGG MetaCyc metabolic pathway
PRIAM PDB structures PDBsum
Gene Ontology EGO
hydroxy-Δ-5-steroid dehydrogenase,
3β- and steroid Δ-isomerase 1
Identifiers
Symbol HSD3B1
Alt. symbols HSDB3, HSD3B
Entrez HUGO OMIM RefSeq UniProt EC number Locus p13-p11
hydroxy-Δ-5-steroid dehydrogenase,
3β- and steroid Δ-isomerase 2
Identifiers
Symbol HSD3B2
Entrez HUGO OMIM RefSeq UniProt EC number Locus p13.1

3-β-HSD (or 3-β-hydroxysteroid dehydrogenase/Δ-5-4 isomerase) (HSD3B2 genes.

It is also known as delta 5-delta 4-isomerase, which catalyzes the oxidative conversion of delta 5-3 beta- hydroxysteroids to the delta 4-3-keto configuration and is, therefore, essential for the biosynthesis of all classes of hormonal steroids, namely progesterone, glucocorticoids, mineralocorticoids, androgens, and estrogens.[2] The 3-beta HSD complex is responsible for the conversion of:

Reaction

3-β-HSD belongs to the family of oxidoreductases, to be specific, those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. This enzyme participates in c21-steroid hormone metabolism and androgen and estrogen metabolism.

3-β-HSD catalyzes the chemical reaction:

a 3β-hydroxy-Δ5-steroid + NAD+ \rightleftharpoons a 3-oxo-Δ5-steroid + NADH + H+

Thus, the two substrates of this enzyme are 3β-hydroxy-Δ5-steroid and NAD+, whereas its 3 products are 3-oxo-Δ5-steroid, NADH, and H+.

Isozymes

Humans express two 3-β-HSD isozymes, HSD3B1 (type I) and HSD3B2 (type II).[3] The type I isoenzyme is expressed in placenta and peripheral tissues, whereas the type II 3β-HSD isoenzyme is expressed in the adrenal gland, ovary, and testis.

Nomenclature

The systematic name of this enzyme class is 3β-hydroxy-Δ5-steroid:NAD+ 3-oxidoreductase. Other names in common use include:

  • progesterone reductase
  • Δ5-3β-hydroxysteroid dehydrogenase
  • 3β-hydroxy-5-ene steroid dehydrogenase
  • 3β-hydroxy steroid dehydrogenase/isomerase
  • 3β-hydroxy-Δ5-C27-steroid dehydrogenase/isomerase
  • 3β-hydroxy-Δ5-C27-steroid oxidoreductase
  • 3β-hydroxy-5-ene-steroid oxidoreductase
  • steroid-Δ5-3β-ol dehydrogenase
  • 3β-HSDH
  • 5-ene-3β-hydroxysteroid dehydrogenase
  • 3β-hydroxy-5-ene-steroid dehydrogenase

Inhibitors

3-β-HSD is inhibited by trilostane.[4]

Biosynthetic pathway

Clinical significance

A deficiency in the type II form through mutations in HSD3B2 is responsible for a rare form of congenital adrenal hyperplasia.[5] No human condition has yet been linked to a deficiency in the type I enzyme. Its importance in placental progesterone production expression suggests that such a mutation would be embryonically lethal.

See also

  • 3α-Hydroxysteroid dehydrogenase (3α-HSD)

References

Further reading


This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.