ENZYME entry: EC 3.3.2.9

Accepted Name

microsomal epoxide hydrolase

Alternative Name(s)

arene-oxide hydratase

aryl epoxide hydrase

benzo[a]pyrene-4,5-oxide hydratase

cis-epoxide hydrolase

epoxide hydrase

epoxide hydratase

mEH

microsomal epoxide hydrase

microsomal epoxide hydratase

microsomal oxirane/oxetane hydrolase

Reaction catalysed

cis-stilbene oxide + H2O = (1R,2R)-hydrobenzoin
1-(4-methoxyphenyl)-N-methyl-N-[(3-methyloxetan-3-yl)methyl]methanamine + H2O = 2-{[(4-methoxybenzyl)(methyl)amino]methyl}-2-methylpropane-1,3-diol

Comment(s)

This is a key hepatic enzyme that catalyzes the hydrolytic ring opening of oxiranes (epoxides) and oxetanes to give the corresponding diols.
The enzyme is involved in the metabolism of numerous substrates including the stereoselective hydrolytic ring opening of 7-oxabicyclo[4.1.0]hepta-2,4-dienes (arene oxides) to the corresponding trans-dihydrodiols.
The reaction proceeds via a triad mechanism and involves the formation of an hydroxyalkyl-enzyme intermediate.
Five epoxide-hydrolase enzymes have been identified in vertebrates to date: EC 3.3.2.6, EC 3.3.2.7, EC 3.3.2.9, EC 3.3.2.10 and EC 3.3.2.11.
Formerly EC 3.3.2.3, EC 4.2.1.63 and EC 4.2.1.64.

Cross-references

BRENDA

EC2PDB

ExplorEnz

KEGG Ligand Database for Enzyme Nomenclature

IUBMB Enzyme Nomenclature

MEDLINE

MetaCyc

Rhea expert-curated reactions

UniProtKB/Swiss-Prot

All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.

All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.3.2.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.3.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.-.-.-