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.
• Lu AY, Ryan D, Jerina DM, Daly JW, Levin W (1975). "Liver microsomal expoxide hydrase. Solubilization, purification, and characterization". J. Biol. Chem. 250 (20): 8283–8. PMID 240858.
• Oesch F (1974). "Purification and specificity of a human microsomal epoxide hydratase". Biochem. J. 139 (1): 77–88. doi:10.1042/bj1390077. PMC 1166253. PMID 4463951.
• Oesch F, Daly J (1971). "Solubilization, purification, and properties of a hepatic epoxide hydrase". Biochim. Biophys. Acta 227 (3): 692–7. doi:10.1016/0005-2744(71)90018-0. PMID 4998715.
• Bellucci G, Chiappe C, Ingrosso G (1994). "Kinetics and stereochemistry of the microsomal epoxide hydrolase-catalyzed hydrolysis of cis-stilbene oxides". Chirality. 6 (7): 577–82. doi:10.1002/chir.530060711. PMID 7986671.
• Morisseau C, Hammock BD (2005). "Epoxide hydrolases: mechanisms, inhibitor designs, and biological roles". Annu. Rev. Pharmacol. Toxicol. 45: 311–33. doi:10.1146/annurev.pharmtox.45.120403.095920. PMID 15822179.
• Fretland AJ, Omiecinski CJ (2000). "Epoxide hydrolases: biochemistry and molecular biology". Chem. Biol. Interact. 129 (1–2): 41–59. doi:10.1016/S0009-2797(00)00197-6. PMID 11154734.
• Oesch F (1973). "Mammalian epoxide hydrases: inducible enzymes catalysing the inactivation of carcinogenic and cytotoxic metabolites derived from aromatic and olefinic compounds". Xenobiotica 3 (5): 305–40. doi:10.3109/00498257309151525. PMID 4584115.
• Lacourciere GM, Armstrong RN (1994). "Microsomal and soluble epoxide hydrolases are members of the same family of C-X bond hydrolase enzymes". Chem. Res. Toxicol. 7 (2): 121–4. doi:10.1021/tx00038a001. PMID 8199297.
• Newman JW, Morisseau C, Hammock BD (2005). "Epoxide hydrolases: their roles and interactions with lipid metabolism". Prog. Lipid. Res. 44 (1): 1–51. doi:10.1016/j.plipres.2004.10.001. PMID 15748653.