4MC0: Hedycaryol Apo

The biosynthesis of terpenes is catalysed by class I and II terpene cyclases. Here we present structural data from a class I hedycaryol synthase in complex with nerolidol, serving as a surrogate for the reaction intermediate nerolidyl diphosphate. This prefolded ligand allows mapping of the active site and hence the identification of a key carbonyl oxygen of Val179, a highly conserved helix break (G1/2) and its corresponding helix dipole. Stabilising the carbocation at the substrate's C1 position, these elements act in concert to catalyse the 1,10 ring closure, thereby exclusively generating the anti-Markovnikov product. The delineation of a general mechanistic scaffold was confirmed by site-specific mutations. This work serves as a basis for understanding carbocation chemistry in enzymatic reactions and should contribute to future application of these enzymes in organic synthesis.
PDB ID: 4MC0Download
MMDB ID: 117067
PDB Deposition Date: 2013/8/21
Updated in MMDB: 2014/01
Experimental Method:
x-ray diffraction
Resolution: 2.7  Å
Source Organism:
Similar Structures:
Biological Unit for 4MC0: monomeric; determined by author and by software (PISA)
Molecular Components in 4MC0
Label Count Molecule
Protein (1 molecule)
Putative Sesquiterpene Cyclase
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB