Complex structures of MoeN5 with substrate analogues suggest sequential catalytic mechanism

Biochem Biophys Res Commun. 2019 Apr 16;511(4):800-805. doi: 10.1016/j.bbrc.2019.02.131. Epub 2019 Mar 2.


The antibiotic moenomycin A is a phosphoglycerate derivative with a C25-moenocinyl chain and a branched oligosaccharide. Formation of the C25-chain is catalyzed by the enzyme MoeN5 with geranyl pyrophosphate (GPP) and the sugar-linked 2-Z,E-farnesyl-3-phosphoglycerate (FPG) as its substrates. Previous complex crystal structures with GPP and long-chain alkyl glycosides suggested that GPP binds to the S1 site in a similar way as in most other α-helical prenyltransferases (PTs), and FPG is likely to assume a bent conformation in the S2 site. However, two FPG derivatives synthesized in the current study were found in the S1 site rather than S2 in their complex crystal structures with MoeN5. Apparently S1 is the preferred site for prenyl-containing ligand, and S2 binding may proceed only after S1 is occupied. Thus, like most trans-type PTs, MoeN5 may employ a sequential ionization-condensation-elimination mechanism that involves a carbocation intermediate.

Keywords: Antibiotics biosynthesis; Prenyltransferase; Sso7d protein tag; X-ray crystallography; moenomycin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2,3-Diphosphoglycerate / chemistry
  • 2,3-Diphosphoglycerate / metabolism
  • Amino Acid Sequence
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Bambermycins / metabolism
  • Crystallography, X-Ray
  • Dimethylallyltranstransferase / chemistry
  • Dimethylallyltranstransferase / metabolism*
  • Molecular Docking Simulation
  • Protein Conformation
  • Sequence Alignment
  • Streptomyces / chemistry
  • Streptomyces / metabolism*
  • Substrate Specificity


  • Bacterial Proteins
  • Bambermycins
  • 2,3-Diphosphoglycerate
  • moenomycin A
  • Dimethylallyltranstransferase