Microsomal epoxide hydrolase

Microsomal epoxide hydrolase
Identifiers
EC number	3.3.2.9
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

In enzymology, a microsomal epoxide hydrolase (EC 3.3.2.9) is an enzyme that catalyzes the chemical reaction

cis-stilbene oxide + H₂O $\rightleftharpoons$ (+)-(1R,2R)-1,2-diphenylethane-1,2-diol

Thus, the two substrates of this enzyme are cis-stilbene oxide and H₂O, whereas its product is (+)-(1R,2R)-1,2-diphenylethane-1,2-diol.

This enzyme belongs to the family of hydrolases, specifically those acting on ether bonds (ether hydrolases). The systematic name of this enzyme class is cis-stilbene-oxide hydrolase. Other names in common use include epoxide hydratase (ambiguous), microsomal epoxide hydratase (ambiguous), epoxide hydrase, microsomal epoxide hydrase, arene-oxide hydratase (ambiguous), benzo[a]pyrene-4,5-oxide hydratase, benzo(a)pyrene-4,5-epoxide hydratase, aryl epoxide hydrase (ambiguous), cis-epoxide hydrolase, and mEH. This enzyme participates in metabolism of xenobiotics by cytochrome p450.

It should also be noted that this class of enzymes plays a role in the uptake of bile salts within the large intestine. It functions as a Na+ dependent transporter.

References

• Boyer, P.D. (Ed.), The Enzymes, 3rd ed., vol. 7, Academic Press, New York, 1972, p. 199-212.