E. coli cells expressing the Baeyer-Villiger monooxygenase 'MO14' (ro03437) from Rhodococcus jostii RHA1 catalyse the gram-scale resolution of a bicyclic ketone in a fermentor

Org Biomol Chem. 2015 Feb 14;13(6):1897-903. doi: 10.1039/c4ob01441c.

Abstract

The Baeyer-Villiger monooxygenase (BVMO) 'MO14' from Rhodococcus jostii RHA1, is an enantioselective BVMO that catalyses the resolution of the model ketone substrate bicyclo[3.2.0]hept-2-en-6-one to the (1S,5R)-2-oxa lactone and the residual (1S,5R)-substrate enantiomer. This regio-plus enantioselective behaviour is highly unusual for BVMOs, which often perform enantiodivergent biotransformations of this substrate. The scaleability of the transformation was investigated using fermentor-based experiments, in which variables including gene codon optimisation, temperature and substrate concentration were investigated. E. coli cells expressing MO14 catalysed the resolution of bicyclo[3.2.0]hept-2-en-6-one to yield (1S,5R)-2-oxa lactone of >99% ee and (1S,5R)-ketone of 96% ee after 14 h at a temperature of 16 °C and a substrate concentration of 0.5 g L(-1) (4.5 mM). MO14 is thus a promising biocatalyst for the production of enantio-enriched ketones and lactones derived from the [3.2.0] platform.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biocatalysis
  • Bioreactors*
  • Escherichia coli / cytology
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Gene Expression Regulation, Enzymologic / genetics
  • Ketones / chemistry
  • Ketones / metabolism*
  • Molecular Conformation
  • Oxygenases / chemistry
  • Oxygenases / genetics*
  • Oxygenases / metabolism
  • Rhodococcus / enzymology*
  • Rhodococcus / metabolism
  • Substrate Specificity

Substances

  • Ketones
  • Oxygenases
  • cyclohexanone oxygenase