4KE4

Elucidation of the structure and reaction mechanism of Sorghum bicolor hydroxycinnamoyltransferase and its structural relationship to other CoA-dependent transferases and synthases


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.012 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Elucidation of the structure and reaction mechanism of sorghum hydroxycinnamoyltransferase and its structural relationship to other coenzyme a-dependent transferases and synthases.

Walker, A.M.Hayes, R.P.Youn, B.Vermerris, W.Sattler, S.E.Kang, C.

(2013) Plant Physiol. 162: 640-651

  • DOI: 10.1104/pp.113.217836
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Hydroxycinnamoyltransferase (HCT) from sorghum (Sorghum bicolor) participates in an early step of the phenylpropanoid pathway, exchanging coenzyme A (CoA) esterified to p-coumaric acid with shikimic or quinic acid as intermediates in the biosynthesis ...

    Hydroxycinnamoyltransferase (HCT) from sorghum (Sorghum bicolor) participates in an early step of the phenylpropanoid pathway, exchanging coenzyme A (CoA) esterified to p-coumaric acid with shikimic or quinic acid as intermediates in the biosynthesis of the monolignols coniferyl alcohol and sinapyl alcohol. In order to elucidate the mode of action of this enzyme, we have determined the crystal structures of SbHCT in its apo-form and ternary complex with shikimate and p-coumaroyl-CoA, which was converted to its product during crystal soaking. The structure revealed the roles of threonine-36, serine-38, tyrosine-40, histidine-162, arginine-371, and threonine-384 in catalysis and specificity. Based on the exact chemistry of p-coumaroyl-CoA and shikimic acid in the active site and an analysis of kinetic and thermodynamic data of the wild type and mutants, we propose a role for histidine-162 and threonine-36 in the catalytic mechanism of HCT. Considering the calorimetric data, substrate binding of SbHCT should occur sequentially, with p-coumaroyl-CoA binding prior to the acyl acceptor molecule. While some HCTs can use both shikimate and quinate as an acyl acceptor, SbHCT displays low activity toward quinate. Comparison of the structure of sorghum HCT with the HCT involved in chlorogenic acid synthesis in coffee (Coffea canephora) revealed many shared features. Taken together, these observations explain how CoA-dependent transferases with similar structural features can participate in different biochemical pathways across species.


    Organizational Affiliation

    School of Molecular Biosciences, Washington State University, Pullman, Washington 99164, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase
A
448Sorghum bicolorMutation(s): 0 
Find proteins for C5XXB7 (Sorghum bicolor)
Go to UniProtKB:  C5XXB7
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
PG4
Query on PG4

Download SDF File 
Download CCD File 
A
TETRAETHYLENE GLYCOL
C8 H18 O5
UWHCKJMYHZGTIT-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.012 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.182 
  • Space Group: P 65
Unit Cell:
Length (Å)Angle (°)
a = 135.947α = 90.00
b = 135.947β = 90.00
c = 64.039γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
HKL-2000data scaling
BOSdata collection
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-05-15
    Type: Initial release
  • Version 1.1: 2013-06-19
    Type: Database references