Reaction: cis-stilbene oxide + H2O = (+)-(1R,2R)-1,2-diphenylethane-1,2-diol
Other name(s): epoxide hydratase (ambiguous); microsomal epoxide hydratase; 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; mEH
Systematic name: cis-stilbene-oxide hydrolase
Comments: This is a key hepatic enzyme that is involved in the metabolism of numerous xenobiotics, such as 1,3-butadiene oxide, styrene oxide and the polycyclic aromatic hydrocarbon benzo[a]pyrene 4,5-oxide . In a series of oxiranes with a lipophilic substituent of sufficient size (styrene oxides), monosubstituted as well as 1,1- and cis-1,2-disubstituted oxiranes serve as substrates or inhibitors of the enzyme. However, trans-1,2-disubstituted, tri-and tetra-substituted oxiranes are not substrates . The reaction involves the formation of an hydroxyalkylenzyme intermediate . In vertebrates, five epoxide-hydrolase enzymes have been identified to date: EC 22.214.171.124 (leukotriene-A4 hydrolase), EC 126.96.36.199 (hepoxilin-epoxide hydrolase), EC 188.8.131.52 (microsomal epoxide hydrolase), EC 184.108.40.206 (soluble epoxide hydrolase) and EC 220.127.116.11 (cholesterol-5,6-oxide hydrolase) .
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
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