Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Standalone Viewers  
Protein Workshop | Ligand Explorer

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 126247.85 
• Atom Count: 8904 
• Residue Count: 1092 
• Unique protein chains: 1

1D4A

CRYSTAL STRUCTURE OF HUMAN NAD[P]H-QUINONE OXIDOREDUCTASE AT 1.7 A RESOLUTION

• DOI: 10.2210/pdb1D4A/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli


• Deposited: 1999-10-01 Released: 1999-10-15 
• Deposition Author(s): Faig, M., Bianchet, M.A., Chen, S., Winski, S., Ross, D., Amzel, L.M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.7 Å
• R-Value Free: 0.253 
• R-Value Work: 0.209 

Literature

Structures of recombinant human and mouse NAD(P)H:quinone oxidoreductases: species comparison and structural changes with substrate binding and release.

Faig, M., Bianchet, M.A., Talalay, P., Chen, S., Winski, S., Ross, D., Amzel, L.M.

(2000) Proc.Natl.Acad.Sci.USA 97: 3177-3182

• PubMed: 10706635 
• DOI: 10.1073/pnas.050585797
• Primary Citation of Related Structures:  
  1DXQ, 1DXO
• Also Cited By: 1H69, 1H66


• PubMed Abstract: 
  

NAD(P)H/quinone acceptor oxidoreductase (QR1, NQO1, formerly DT-diaphorase; EC ) protects animal cells from the deleterious and carcinogenic effects of quinones and other electrophiles. In this paper we report the apoenzyme structures of human (at 1.7-A resolution) and mouse (2.8 A) QR1 and the complex of the human enzyme with the substrate duroquinone (2.5 A) (2,3,5, 6-tetramethyl-p-benzoquinone). In addition to providing a description and rationale of the structural and catalytic differences among several species, these structures reveal the changes that accompany substrate or cofactor (NAD) binding and release. Tyrosine-128 and the loop spanning residues 232-236 close the binding site, partially occupying the space left vacant by the departing molecule (substrate or cofactor). These changes highlight the exquisite control of access to the catalytic site that is required by the ping-pong mechanism in which, after reducing the flavin, NAD(P)(+) leaves the catalytic site and allows substrate to bind at the vacated position. In the human QR1-duroquinone structure one ring carbon is significantly closer to the flavin N5, suggesting a direct hydride transfer to this atom.

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Related Citations: 

• The Three-Dimensional Structure of NAD(P)H:quinone Reductase, a Flavoprotein Involved in Cancer Chemoprotection and Chemotherapy: Mechanism of Two-Electron Reduction
  Li, R.,Bianchet, M.A.,Talalay, P.,Amzel, L.M.
  (1995) Proc.Natl.Acad.Sci.USA 92: 8846
• Crystal Structure of Human Quinone Reductase type 2, a Metalloprotein
  Foster, C.,Bianchet, M.A.,Talalay, P.,Zhao, Q.,Amzel, L.M.
  (1999) Biochemistry 38: 9881
• Structure and Mechanism of Cytosolic Quinone Reductase
  Bianchet, M.A.,Foster, C.,Faig, M.,Talalay, P.,Amzel, L.M.
  (1999) Biochem.Soc.Trans. 27: 610




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Organizational Affiliation: 

Departments of Biophysics and Biophysical Chemistry and Pharmacology and Molecular Sciences, Johns Hopkins Medical School, Baltimore, MD 21205, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
QUINONE REDUCTASE	A, B, C, D	273	Homo sapiens	Mutation(s): 0  Gene Names: NQO1 (DIA4, NMOR1) EC: 1.6.5.2
Find proteins for P15559 (Homo sapiens) Go to Gene View: NQO1 Go to UniProtKB:  P15559

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
FAD	A, B, C, D	FLAVIN-ADENINE DINUCLEOTIDE C27 H33 N9 O15 P2 VWWQXMAJTJZDQX-UYBVJOGSSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.7 Å
• R-Value Free: 0.253 
• R-Value Work: 0.209 
• Space Group: P 1

Unit Cell:

Length (Å)	Angle (°)
a = 55.678	α = 77.04
b = 57.032	β = 76.72
c = 97.402	γ = 86.89

Software Package:

Software Name	Purpose
AMoRE	phasing
DENZO	data reduction
CCP4	data scaling
CNS	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1999-10-01 
• Released Date: 1999-10-15 
• Deposition Author(s): Faig, M., Bianchet, M.A., Chen, S., Winski, S., Ross, D., Amzel, L.M.

Revision History 

• Version 1.0: 1999-10-15
  Type: Initial release
• Version 1.1: 2008-04-27
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance
• Version 1.3: 2014-11-12
  Type: Structure summary