Limonene-1,2-epoxide hydrolase from Rhodococcus erythropolis DCL14, an enzy
me involved in the limonene metabolism of this microorganism, catalyzes the
enantioselective hydrolysis of 1-methylcyclohexene oxide. (1R,2S)-1-Methyl
cyclohexene oxide was the preferred substrate and it was mainly hydrolyzed
to (1S,2S)-1 methylcyclohexane-1,2-diol, while (1S,2R)-1-methylcyclohexene
oxide was converted more slowly and mainly yielded (1R,2R)-1-methylcyclohex
ane-1,2-diol. The reaction proceeded with a high regioselectivity (C1:C2, 8
5,15). (H2O)-O-18-labelling experiments confirmed that the nucleophile was
mainly incorporated at the most substituted carbon atom, suggesting that li
monene-1,2-epoxide hydrolase uses an acid-catalyzed enzyme mechanism. (C) 1
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