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Enantiocomplementary Epoxidation Reactions Catalyzed by an Engineered Cofactor-Independent Non-natural Peroxygenase.

ABSTRACT: Peroxygenases are heme-dependent enzymes that use peroxide-borne oxygen to catalyze a wide range of oxyfunctionalization reactions. Herein, we report the engineering of an unusual cofactor-independent peroxygenase based on a promiscuous tautomerase that accepts different hydroperoxides (t-BuOOH and H2 O2 ) to accomplish enantiocomplementary epoxidations of various α,β-unsaturated aldehydes (citral and substituted cinnamaldehydes), providing access to both enantiomers of the corresponding α,β-epoxy-aldehydes. High conversions (up to 98 %), high enantioselectivity (up to 98 % ee), and good product yields (50-80 %) were achieved. The reactions likely proceed via a reactive enzyme-bound iminium ion intermediate, allowing tweaking of the enzyme's activity and selectivity by protein engineering. Our results underscore the potential of catalytic promiscuity for the engineering of new cofactor-independent oxidative enzymes.

SUBMITTER: Xu G

PROVIDER: S-EPMC7317984 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Stereospecific Epoxidation of Limonene Catalyzed by Peroxygenase from Oat Seeds.

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| S-EPMC8469233 | biostudies-literature

Fast and Specific Peroxygenase Reactions Catalyzed by Fungal Mono-Copper Enzymes.

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