3W5H

Ultra-high resolution structure of NADH-cytochrome b5 reductase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.78 Å
  • R-Value Free: 0.144 
  • R-Value Work: 0.126 
  • R-Value Observed: 0.127 

wwPDB Validation   3D Report Full Report


This is version 1.2 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: https://doi.org/10.1016/j.jmb.2013.06.010
  • Primary Citation of Related Structures:  
    3W2E, 3W2F, 3W2G, 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 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:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
NADH-cytochrome b5 reductase 3272Sus scrofaMutation(s): 0 
Gene Names: CYB5R3DIA1
EC: 1.6.2.2
UniProt
Find proteins for P83686 (Sus scrofa)
Explore P83686 
Go to UniProtKB:  P83686
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP83686
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.78 Å
  • R-Value Free: 0.144 
  • R-Value Work: 0.126 
  • R-Value Observed: 0.127 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 48.48α = 90
b = 72.108β = 90
c = 84.908γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
MOLREPphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-07-17
    Type: Initial release
  • Version 1.1: 2014-04-30
    Changes: Database references
  • Version 1.2: 2024-03-20
    Changes: Data collection, Database references, Derived calculations