Kinetic Resolution of sec-Thiols by Enantioselective Oxidation with Rationally Engineered 5-(Hydroxymethyl)furfural Oxidase

Angew Chem Int Ed Engl. 2018 Mar 5;57(11):2864-2868. doi: 10.1002/anie.201713189. Epub 2018 Feb 15.

Abstract

Various flavoprotein oxidases were recently shown to oxidize primary thiols. Herein, this reactivity is extended to sec-thiols by using structure-guided engineering of 5-(hydroxymethyl)furfural oxidase (HMFO). The variants obtained were employed for the oxidative kinetic resolution of racemic sec-thiols, thus yielding the corresponding thioketones and nonreacted R-configured thiols with excellent enantioselectivities (E≥200). The engineering strategy applied went beyond the classic approach of replacing bulky amino acid residues with smaller ones, as the active site was additionally enlarged by a newly introduced Thr residue. This residue established a hydrogen-bonding interaction with the substrates, as verified in the crystal structure of the variant. These strategies unlocked HMFO variants for the enantioselective oxidation of a range of sec-thiols.

Keywords: biocatalysis; enzymes; kinetic resolution; oxidation; thiols.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Furaldehyde / analogs & derivatives*
  • Furaldehyde / metabolism
  • Hydrogen Bonding
  • Kinetics
  • Models, Molecular
  • Mutagenesis, Site-Directed* / methods
  • Oxidation-Reduction
  • Oxidoreductases / genetics
  • Oxidoreductases / metabolism*
  • Point Mutation
  • Stereoisomerism
  • Sulfhydryl Compounds / chemistry
  • Sulfhydryl Compounds / metabolism*

Substances

  • Sulfhydryl Compounds
  • 1-phenylethanethiol
  • 5-hydroxymethylfurfural
  • Furaldehyde
  • Oxidoreductases