5D9W

Dehydroascorbate reductase (OsDHAR) complexed with ASA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6897 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.203 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Structural understanding of the recycling of oxidized ascorbate by dehydroascorbate reductase (OsDHAR) from Oryza sativa L. japonica

Do, H.Kim, I.S.Jeon, B.W.Lee, C.W.Park, A.K.Wi, A.R.Shin, S.C.Park, H.Kim, Y.S.Yoon, H.S.Kim, H.W.Lee, J.H.

(2016) Sci Rep 6: 19498-19498

  • DOI: 10.1038/srep19498
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Dehydroascorbate reductase (DHAR) is a key enzyme involved in the recycling of ascorbate, which catalyses the glutathione (GSH)-dependent reduction of oxidized ascorbate (dehydroascorbate, DHA). As a result, DHAR regenerates a pool of reduced ascorba ...

    Dehydroascorbate reductase (DHAR) is a key enzyme involved in the recycling of ascorbate, which catalyses the glutathione (GSH)-dependent reduction of oxidized ascorbate (dehydroascorbate, DHA). As a result, DHAR regenerates a pool of reduced ascorbate and detoxifies reactive oxygen species (ROS). In previous experiments involving transgenic rice, we observed that overexpression of DHAR enhanced grain yield and biomass. Since the structure of DHAR is not available, the enzymatic mechanism is not well-understood and remains poorly characterized. To elucidate the molecular basis of DHAR catalysis, we determined the crystal structures of DHAR from Oryza sativa L. japonica (OsDHAR) in the native, ascorbate-bound, and GSH-bound forms and refined their resolutions to 1.9, 1.7, and 1.7 Å, respectively. These complex structures provide the first information regarding the location of the ascorbate and GSH binding sites and their interacting residues. The location of the ascorbate-binding site overlaps with the GSH-binding site, suggesting a ping-pong kinetic mechanism for electron transfer at the common Cys20 active site. Our structural information and mutagenesis data provide useful insights into the reaction mechanism of OsDHAR against ROS-induced oxidative stress in rice.


    Organizational Affiliation

    Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 406-840, Republic of Korea.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Dehydroascorbate reductase
A
230Oryza sativa subsp. japonicaMutation(s): 1 
Gene Names: DHAR1 (DHAR)
EC: 2.5.1.18
Find proteins for Q65XA0 (Oryza sativa subsp. japonica)
Go to UniProtKB:  Q65XA0
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ASC
Query on ASC

Download SDF File 
Download CCD File 
A
ASCORBIC ACID
C6 H8 O6
CIWBSHSKHKDKBQ-JLAZNSOCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6897 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.203 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 46.848α = 90.00
b = 47.279β = 108.23
c = 50.992γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data processing
MOLREPphasing
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data

  • Deposited Date: 2015-08-19 
  • Released Date: 2016-02-03 
  • Deposition Author(s): Do, H., Lee, J.H.

Funding OrganizationLocationGrant Number
Korea Polar Research InstituteKorea, Republic OfPE15070
Rural Development AdministrationKorea, Republic OfPJ011122

Revision History 

  • Version 1.0: 2016-02-03
    Type: Initial release