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Updated: May 17, 2026

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
Structural characterization of a D-isomer specific 2-hydroxyacid dehydrogenase from Lactobacillus delbrueckii ssp.
Simon J Holton1, Madhankumar Anandhakrishnan, Arie Geerlof
1EMBL c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany. sjholton@googlemail.com
Abstract:
Hydroxyacid dehydrogenases, responsible for the stereospecific conversion of 2-keto acids to 2-hydroxyacids in lactic acid producing bacteria, have a range of biotechnology applications including antibiotic synthesis, flavor development in dairy products and the production of valuable synthons. The genome of Lactobacillus delbrueckii ssp. bulgaricus, a member of the heterogeneous group of lactic acid bacteria, encodes multiple hydroxyacid dehydrogenases whose structural and functional properties remain poorly characterized. Here, we report the apo and coenzyme NAD⁺ complexed crystal structures of the L. bulgaricusD-isomer specific 2-hydroxyacid dehydrogenase, D2-HDH. Comparison with closely related members of the NAD-dependent dehydrogenase family reveals that whilst the D2-HDH core fold is structurally conserved, the substrate-binding site has a number of non-canonical features that may influence substrate selection and thus dictate the physiological function of the enzyme.
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