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Inverting the Stereoselectivity of an NADH-Dependent Imine-Reductase Variant.

ABSTRACT: Imine reductases (IREDs) offer biocatalytic routes to chiral amines and have a natural preference for the NADPH cofactor. In previous work, we reported enzyme engineering of the (R)-selective IRED from Myxococcus stipitatus (NADH-IRED-Ms) yielding a NADH-dependent variant with high catalytic efficiency. However, no IRED with NADH specificity and (S)-selectivity in asymmetric reductions has yet been reported. Herein, we applied semi-rational enzyme engineering to switch the selectivity of NADH-IRED-Ms. The quintuple variant A241V/H242Y/N243D/V244Y/A245L showed reverse stereopreference in the reduction of the cyclic imine 2-methylpyrroline compared to the wild-type and afforded the (S)-amine product with >99 % conversion and 91 % enantiomeric excess. We also report the crystal-structures of the NADPH-dependent (R)-IRED-Ms wild-type enzyme and the NADH-dependent NADH-IRED-Ms variant and molecular dynamics (MD) simulations to rationalize the inverted stereoselectivity of the quintuple variant.

SUBMITTER: Stockinger P

PROVIDER: S-EPMC9297850 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Inverting the Stereoselectivity of an NADH-Dependent Imine-Reductase Variant.

Stockinger Peter P Borlinghaus Niels N Sharma Mahima M Aberle Benjamin B Grogan Gideon G Pleiss Jürgen J Nestl Bettina M BM

ChemCatChem 20211022 24

Imine reductases (IREDs) offer biocatalytic routes to chiral amines and have a natural preference for the NADPH cofactor. In previous work, we reported enzyme engineering of the (R)-selective IRED from Myxococcus stipitatus (NADH-IRED-Ms) yielding a NADH-dependent variant with high catalytic efficiency. However, no IRED with NADH specificity and (S)-selectivity in asymmetric reductions has yet been reported. Herein, we applied semi-rational enzyme engineering to switc ...[more]

PMID: 35873105

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Dataset Information

Inverting the Stereoselectivity of an NADH-Dependent Imine-Reductase Variant.

Publications

Inverting the Stereoselectivity of an NADH-Dependent Imine-Reductase Variant.

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