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Engineering of Thermostable ?-Hydroxyacid Dehydrogenase for the Asymmetric Reduction of Imines.

ABSTRACT: The ?-hydroxyacid dehydrogenase from Thermocrinus albus (Ta-?HAD), which catalyzes the NADP⁺ -dependent oxidation of ?-hydroxyacids, was engineered to accept imines as substrates. The catalytic activity of the proton-donor variant K189D was further increased by the introduction of two nonpolar flanking residues (N192?L, N193?L). Engineering the putative alternative proton donor (D258S) and the gate-keeping residue (F250?A) led to a switched substrate specificity as compared to the single and triple variants. The two most active Ta-?HAD variants were applied to biocatalytic asymmetric reductions of imines at elevated temperatures and enabled enhanced product formation at a reaction temperature of 50?°C.

SUBMITTER: Stockinger P

PROVIDER: S-EPMC7756219 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Engineering of Thermostable β-Hydroxyacid Dehydrogenase for the Asymmetric Reduction of Imines.

Stockinger Peter P Schelle Luca L Schober Benedikt B Buchholz Patrick C F PCF Pleiss Jürgen J Nestl Bettina M BM

Chembiochem : a European journal of chemical biology 20200916 24

The β-hydroxyacid dehydrogenase from Thermocrinus albus (Ta-βHAD), which catalyzes the NADP<sup>+</sup> -dependent oxidation of β-hydroxyacids, was engineered to accept imines as substrates. The catalytic activity of the proton-donor variant K189D was further increased by the introduction of two nonpolar flanking residues (N192 L, N193 L). Engineering the putative alternative proton donor (D258S) and the gate-keeping residue (F250 A) led to a switched substrate specificity as compared to the sin ...[more]

PMID: 32939899

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