Blee_1995_Eur.J.Biochem_230_229

Soybean fatty acid epoxide hydrolase (EC 3.3.2.3) was found to possess remarkable and unique stereochemical features. After complete hydrolysis, this enzyme converts racemic or enantiomerically enriched cis-9,10-epoxy-12(Z)-octadecenoic and cis-12,13-epoxyocta-9(Z)-decenoic acids, i.e. the two regioisomers of linoleic acid monoepoxides, into their corresponding 9R, 10R- and 12R, 13R-dihydrodiols with a high enantiomeric excess (> 90%). A straightforward chiral-phase HPLC technique was developed that gives an easy access to the stereochemistry of these reaction products. These results are discussed in terms of a possible model for the substrate binding site of this enzyme.