3W2G

Crystal structure of fully reduced form of NADH-cytochrome b5 reductase from pig liver


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.68 Å
  • R-Value Free: 0.169 
  • R-Value Work: 0.150 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Elucidations of the catalytic cycle of NADH-cytochrome b5 reductase by X-ray crystallography: new insights into regulation of efficient electron transfer

Yamada, M.Tamada, T.Takeda, K.Matsumoto, F.Ohno, H.Kosugi, M.Takaba, K.Shoyama, Y.Kimura, S.Kuroki, R.Miki, K.

(2013) J.Mol.Biol. 425: 4295-4306

  • DOI: 10.1016/j.jmb.2013.06.010
  • Primary Citation of Related Structures:  3W2E, 3W2F, 3W2H, 3W2I, 3W5H

  • PubMed Abstract: 
  • NADH-Cytochrome b5 reductase (b5R), a flavoprotein consisting of NADH and flavin adenine dinucleotide (FAD) binding domains, catalyzes electron transfer from the two-electron carrier NADH to the one-electron carrier cytochrome b5 (Cb5). The crystal s ...

    NADH-Cytochrome b5 reductase (b5R), a flavoprotein consisting of NADH and flavin adenine dinucleotide (FAD) binding domains, catalyzes electron transfer from the two-electron carrier NADH to the one-electron carrier cytochrome b5 (Cb5). The crystal structures of both the fully reduced form and the oxidized form of porcine liver b5R were determined. In the reduced b5R structure determined at 1.68Å resolution, the relative configuration of the two domains was slightly shifted in comparison with that of the oxidized form. This shift resulted in an increase in the solvent-accessible surface area of FAD and created a new hydrogen-bonding interaction between the N5 atom of the isoalloxazine ring of FAD and the hydroxyl oxygen atom of Thr66, which is considered to be a key residue in the release of a proton from the N5 atom. The isoalloxazine ring of FAD in the reduced form is flat as in the oxidized form and stacked together with the nicotinamide ring of NAD(+). Determination of the oxidized b5R structure, including the hydrogen atoms, determined at 0.78Å resolution revealed the details of a hydrogen-bonding network from the N5 atom of FAD to His49 via Thr66. Both of the reduced and oxidized b5R structures explain how backflow in this catalytic cycle is prevented and the transfer of electrons to one-electron acceptors such as Cb5 is accelerated. Furthermore, crystallographic analysis by the cryo-trapping method suggests that re-oxidation follows a two-step mechanism. These results provide structural insights into the catalytic cycle of b5R.


    Organizational Affiliation

    Molecular Biology Research Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
NADH-cytochrome b5 reductase 3
A
271Sus scrofaGene Names: CYB5R3 (DIA1)
EC: 1.6.2.2
Find proteins for P83686 (Sus scrofa)
Go to Gene View: CYB5R3
Go to UniProtKB:  P83686
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FAD
Query on FAD

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

Download SDF File 
Download CCD File 
A
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.68 Å
  • R-Value Free: 0.169 
  • R-Value Work: 0.150 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 58.164α = 90.00
b = 72.689β = 90.00
c = 86.630γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
PHENIXphasing
PHENIXmodel building
ADSCdata collection
PHENIXrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-07-17
    Type: Initial release
  • Version 1.1: 2014-04-30
    Type: Database references