Laboratory Evolved Biocatalysts for Stereoselective Syntheses of Substituted Benzaldehyde Cyanohydrins (pages 58–61)
Zhibin Liu, Beate Pscheidt, Manuela Avi, Richard Gaisberger, Franz Stefan Hartner, Christian Schuster, Wolfgang Skranc, Karl Gruber and Anton Glieder
Article first published online: 4 DEC 2007 | DOI: 10.1002/cbic.200700514
Random mutagenesis and recombination of PaHNL5 was carried out in Pichia pastoris by employment of an overlap extension PCR-based strategy. New fast and stereoselective enzyme variants were obtained, and these led to improved turnover rates with the nonnatural substrate 2-chlorobenzaldehyde. A new catalyst combining all favorable mutations was generated, and even very small amounts of this variant enabled complete conversion of 2-chlorobenzaldehyde into the (R)-hydroxynitrile with >99 % ee in only 4 h.