Switching the Regioselectivity of a Cyclohexanone Monooxygenase toward (+)-trans-Dihydrocarvone by Rational Protein Design

ACS Chem Biol. 2016 Jan 15;11(1):38-43. doi: 10.1021/acschembio.5b00723. Epub 2015 Nov 9.

Abstract

The regioselectivity of the Baeyer-Villiger monooxygenase-catalyzed oxidation is governed mostly by electronic effects leading to the migration of the higher substituted residue. However, in some cases, substrate binding occurs in a way that the less substituted residue lies in an antiperiplanar orientation to the peroxy bond in the Criegee intermediate yielding in the formation of the "abnormal" lactone product. We are the first to demonstrate a complete switch in the regioselectivity of the BVMO from Arthrobacter sp. (CHMOArthro) as exemplified for (+)-trans-dihydrocarvone by redesigning the active site of the enzyme. In the designed triple mutant, the substrate binds in an inverted orientation leading to a ratio of 99:1 in favor of the normal lactone instead of exclusive formation of the abnormal lactone in case of the wild type enzyme. In order to validate our computational study, the beneficial mutations were successfully transferred to the CHMO from Acinetobacter sp. (CHMOAcineto), again yielding in a complete switch of regioselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinobacteria / enzymology
  • Actinobacteria / genetics
  • Arthrobacter / enzymology
  • Arthrobacter / genetics
  • Catalytic Domain
  • Cyclohexane Monoterpenes
  • Drug Design*
  • Models, Molecular
  • Molecular Docking Simulation*
  • Monoterpenes / chemistry*
  • Mutation
  • Oxygenases / chemistry*
  • Oxygenases / genetics
  • Oxygenases / metabolism*
  • Stereoisomerism
  • Substrate Specificity

Substances

  • Cyclohexane Monoterpenes
  • Monoterpenes
  • Oxygenases
  • cyclohexanone oxygenase
  • dihydrocarvone