-!- Catalyzes the hydrolysis of trans-substituted epoxides, such as trans-stilbene oxide, as well as various aliphatic epoxides derived from fatty-acid metabolism. -!- It is involved in the metabolism of arachidonic epoxides (epoxyeicosatrienoic acids; EETs) and linoleic acid epoxides. -!- The enzyme from mammals is a bifunctional enzyme: the C-terminal domain exhibits epoxide-hydrolase activity and the N-terminal domain has the activity of EC 3.1.3.76. -!- Like EC 3.3.2.9, it is probable that the reaction involves the formation of an hydroxyalkyl-enzyme intermediate. -!- The enzyme can also use leukotriene A(4), the substrate of EC 3.3.2.6, but it forms 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid rather than leukotriene B(4) as the product. -!- Formerly EC 3.3.2.3, EC 4.2.1.63 and EC 4.2.1.64.