Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

5.3.3.1

RLRdb entry

RL00033

Organisms

Homo sapiens (Human) (9606_human)

Synonyms

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 1;
Short=3-beta-HSD I;
Trophoblast antigen FDO161G;
3-beta-hydroxy-Delta(5)-steroid dehydrogenase;
EC=1.1.1.145;
3-beta-hydroxy-5-ene steroid dehydrogenase;
Progesterone reductase;
Steroid Delta-isomerase;
EC=5.3.3.1;
Delta-5-3-ketosteroid isomerase;

Key words

Direct protein sequencing, Endoplasmic reticulum, Isomerase, Membrane, Mitochondrion, Multifunctional enzyme, NAD, Oxidoreductase, Polymorphism, Steroidogenesis, Transmembrane

Links to iHOP

P14060

Function

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.

Subcellular localization

Endoplasmic reticulum membrane; Single-pass membrane protein. Mitochondrion membrane; Single-pass membrane protein

Catalytic activity

A 3-oxo-Delta(5)-steroid = a 3-oxo-Delta(4)-steroid
A 3-beta-hydroxy-Delta(5)-steroid + NAD(+) = a 3-oxo-Delta(5)-steroid + NADH

Gene ontology

F:binding
F:3-beta-hydroxy-delta5-steroid dehydrogenase...
F:steroid delta-isomerase activity
P:oxidation reduction
P:androgen biosynthetic process
C:microsome
C:integral to membrane
C:mitochondrial intermembrane space
P:estrogen biosynthetic process
C:smooth endoplasmic reticulum membrane
P:C21-steroid hormone biosynthetic process
C:mitochondrial inner membrane

Tissue specificity

Placenta and skin. Predominantly expressed in mammary gland tissue.

Fasta

>P14060 : length: 373
MTGWSCLVTGAGGFLGQRIIRLLVKEKELKEIRVLDKAFGPELREEFSKLQNKTKLTVLE
GDILDEPFLKRACQDVSVIIHTACIIDVFGVTHRESIMNVNVKGTQLLLEACVQASVPVF
IYTSSIEVAGPNSYKEIIQNGHEEEPLENTWPAPYPHSKKLAEKAVLAANGWNLKNGGTL
YTCALRPMYIYGEGSRFLSASINEALNNNGILSSVGKFSTVNPVYVGNVAWAHILALRAL
QDPKKAPSIRGQFYYISDDTPHQSYDNLNYTLSKEFGLRLDSRWSFPLSLMYWIGFLLEI
VSFLLRPIYTYRPPFNRHIVTLSNSVFTFSYKKAQRDLAYKPLYSWEEAKQKTVEWVGSL
VDRHKETLKSKTQ



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  Last Modified: 2009-03-24  
  Design by Zhao Min