1QRD

QUINONE REDUCTASE/FAD/CIBACRON BLUE/DUROQUINONE COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.188 
  • R-Value Observed: 0.188 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The three-dimensional structure of NAD(P)H:quinone reductase, a flavoprotein involved in cancer chemoprotection and chemotherapy: mechanism of the two-electron reduction.

Li, R.Bianchet, M.A.Talalay, P.Amzel, L.M.

(1995) Proc Natl Acad Sci U S A 92: 8846-8850

  • DOI: 10.1073/pnas.92.19.8846
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Quinone reductase [NAD(P)H:(quinone acceptor) oxidoreductase, EC 1.6.99.2], also called DT diaphorase, is a homodimeric FAD-containing enzyme that catalyzes obligatory NAD(P)H-dependent two-electron reductions of quinones and protects cells against t ...

    Quinone reductase [NAD(P)H:(quinone acceptor) oxidoreductase, EC 1.6.99.2], also called DT diaphorase, is a homodimeric FAD-containing enzyme that catalyzes obligatory NAD(P)H-dependent two-electron reductions of quinones and protects cells against the toxic and neoplastic effects of free radicals and reactive oxygen species arising from one-electron reductions. These two-electron reductions participate in the reductive bioactivation of cancer chemotherapeutic agents such as mitomycin C in tumor cells. Thus, surprisingly, the same enzymatic reaction that protects normal cells activates cytotoxic drugs used in cancer chemotherapy. The 2.1-A crystal structure of rat liver quinone reductase reveals that the folding of a portion of each monomer is similar to that of flavodoxin, a bacterial FMN-containing protein. Two additional portions of the polypeptide chains are involved in dimerization and in formation of the two identical catalytic sites to which both monomers contribute. The crystallographic structures of two FAD-containing enzyme complexes (one containing NADP+, the other containing duroquinone) suggest that direct hydride transfers from NAD(P)H to FAD and from FADH2 to the quinone [which occupies the site vacated by NAD(P)H] provide a simple rationale for the obligatory two-electron reductions involving a ping-pong mechanism.


    Organizational Affiliation

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
QUINONE-REDUCTASE
A, B
273Rattus rattusMutation(s): 0 
EC: 1.6.99.2 (PDB Primary Data), 1.6.5.2 (UniProt)
Find proteins for P05982 (Rattus norvegicus)
Go to UniProtKB:  P05982
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FAD
Query on FAD

Download CCD File 
A, B
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
CBD
Query on CBD

Download CCD File 
A, B
CIBACRON BLUE
C29 H20 Cl N7 O11 S3
YKCWQPZFAFZLBI-UHFFFAOYSA-N
 Ligand Interaction
DQN
Query on DQN

Download CCD File 
A, B
DUROQUINONE
C10 H12 O2
WAMKWBHYPYBEJY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.188 
  • R-Value Observed: 0.188 
  • Space Group: I 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72α = 90
b = 107β = 92.6
c = 88.4γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
XDSdata reduction
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1996-10-14
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance