Affordable Access

deepdyve-link
Publisher Website

Synthesis of (R)-mandelic acid and (R)-mandelic acid amide by recombinant E. coli strains expressing a (R)-specific oxynitrilase and an arylacetonitrilase.

Authors
  • Müller, Erik1
  • Sosedov, Olga1, 2
  • Gröning, Janosch Alexander David1
  • Stolz, Andreas3
  • 1 Institut für Mikrobiologie, Universität Stuttgart, Allmandring 31, 70569, Stuttgart, Germany. , (Germany)
  • 2 Biochem Labor für chemische Analytik GmbH, Daimlerstr. 5B, 76185, Karlsruhe, Germany. , (Germany)
  • 3 Institut für Mikrobiologie, Universität Stuttgart, Allmandring 31, 70569, Stuttgart, Germany. [email protected] , (Germany)
Type
Published Article
Journal
Biotechnology Letters
Publisher
Springer-Verlag
Publication Date
Jan 01, 2021
Volume
43
Issue
1
Pages
287–296
Identifiers
DOI: 10.1007/s10529-020-02998-8
PMID: 32936375
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

Chiral 2-hydroxycarboxylic acids and 2-hydroxycarboxamides are valuable synthons for the chemical industry. The biocatalytic syntheses of (R)-mandelic acid and (R)-mandelic acid amide by recombinant Escherichia coli clones were studied. Strains were constructed which simultaneously expressed a (R)-specific oxynitrilase (hydroxynitrile lyase) from the plant Arabidopsis thaliana together with the arylacetonitrilase from the bacterium Pseudomonas fluorescens EBC191. In addition, recombinant strains were constructed which expressed a previously described acid tolerant variant of the oxynitrilase and an amide forming variant of the nitrilase. The whole cell catalysts which simultaneously expressed the (R)-specific oxynitrilase and the wild-type nitrilase transformed in slightly acidic buffer systems benzaldehyde plus cyanide preferentially to (R)-mandelic acid with ee-values > 95%. The combination of the (R)-specific oxynitrilase with the amide forming nitrilase variant gave whole cell catalysts which converted at pH-values ≤ pH 5 benzaldehyde plus cyanide with a high degree of enantioselectivity (ee > 90%) to (R)-mandelic acid amide. The acid and the amide forming catalysts also converted chlorinated benzaldehydes with cyanide to chlorinated mandelic acid or chlorinated mandelic acid amides. Efficient systems for the biocatalytic production of (R)-2-hydroxycarboxylic acids and (R)-2-hydroxycarboxamides were generated.

Report this publication

Statistics

Seen <100 times