Structural and Molecular Basis of the Catalytic Mechanism of Geranyl Pyrophosphate C6-Methyltransferase: Creation of an Unprecedented Farnesyl Pyrophosphate C6-Methyltransferase

Angew Chem Int Ed Engl. 2022 Jan 3;61(1):e202111217. doi: 10.1002/anie.202111217. Epub 2021 Nov 23.


Prenyl pyrophosphate methyltransferases enhance the structural diversity of terpenoids. However, the molecular basis of their catalytic mechanisms is poorly understood. In this study, using multiple strategies, we characterized a geranyl pyrophosphate (GPP) C6-methyltransferase, BezA. Biochemical analysis revealed that BezA requires Mg2+ and solely methylates GPP. The crystal structures of BezA and its complex with S-adenosyl homocysteine were solved at 2.10 and 2.56 Å, respectively. Further analyses using site-directed mutagenesis, molecular docking, molecular dynamics simulations, and quantum mechanics/molecular mechanics calculations revealed the molecular basis of the methylation reaction. Importantly, the function of E170 as a catalytic base to complete the methylation reaction was established. We also succeeded in switching the substrate specificity by introducing a W210A substitution, resulting in an unprecedented farnesyl pyrophosphate C6-methyltransferase.

Keywords: biosynthesis; enzyme catalysis; methyltransferase; rational engineering; terpenoids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biocatalysis
  • Crystallography, X-Ray
  • Density Functional Theory
  • Methyltransferases / chemistry
  • Methyltransferases / genetics
  • Methyltransferases / metabolism*
  • Models, Molecular
  • Molecular Structure
  • Polyisoprenyl Phosphates / chemistry
  • Polyisoprenyl Phosphates / metabolism*
  • Sesquiterpenes / chemistry
  • Sesquiterpenes / metabolism*
  • Streptomyces / enzymology
  • Substrate Specificity


  • Polyisoprenyl Phosphates
  • Sesquiterpenes
  • geranyl pyrophosphate
  • farnesyl pyrophosphate
  • Methyltransferases

Supplementary concepts

  • Streptomyces argenteolus