Cobalt substitution of mouse R2 ribonucleotide reductase to model the reactive diferrous state

Experimental Data Snapshot

  • Resolution: 2.40 Å
  • R-Value Free: 0.297 
  • R-Value Work: 0.218 
  • R-Value Observed: 0.218 

wwPDB Validation 

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This is version 1.3 of the entry. See complete history


Cobalt Substitution of Mouse R2 Ribonucleotide Reductase as a Model for Thereactive Diferrous State. Spectroscopic and Structural Evidence for a Ferromagnetically Coupled Dinuclear Cobalt Cluster

Strand, K.R.Karlsen, S.Andersson, K.K.

(2002) J Biol Chem 277: 34229

  • DOI: https://doi.org/10.1074/jbc.M203358200
  • Primary Citation of Related Structures:  
    1H0N, 1H0O

  • PubMed Abstract: 

    The R2 dimer of mouse ribonucleotide reductase contains a dinuclear iron-oxygen cluster and tyrosyl radical/subunit. The dinuclear diferrous form reacts with dioxygen to generate the tyrosyl radical essential for the catalytic reaction that occurs at the R1 dimer. It is important to understand how the reactivity toward oxygen is related to the crystal structure of the dinuclear cluster. For the mouse R2 protein, no structure has been available with a fully occupied dinuclear metal ion site. A cobalt substitution of mouse R2 was performed to produce a good model for the very air-sensitive diferrous form of the enzyme. X-band EPR and light absorption studies (epsilon(550 nm) = 100 mm(-1) cm(-1)/Co(II)) revealed a strong cooperative binding of cobalt to the dinuclear site. In perpendicular mode EPR, the axial signal from mouse R2 incubated with Co(II) showed a typical S = 3/2 Co(II) signal, and its low intensity indicated that the majority of the Co(II) bound to R2 is magnetically coupled. In parallel mode EPR, a typical integer spin signal (M(s) = +/-3) with g approximately 12 is observed at 3.6 K and 10 K, showing that the two Co(II) ions (S = 3/2) in the dinuclear site are ferromagnetically coupled. We have solved the 2.4 A crystal structure of the Co(II)-substituted R2 with a fully occupied dinuclear cluster. The bridging Co(II) carboxylate ligand Glu-267 adopts an altered orientation compared with its counterpart Glu-238 in Escherichia coli R2. This might be important for proper O(2) activation of the more exposed native diferrous site in mouse R2 compared with E. coli R2.

  • Organizational Affiliation

    Department of Biochemistry, University of Oslo, P. O. Box 1041, Blindern, Oslo N-0316, Norway.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
UniProt & NIH Common Fund Data Resources
Find proteins for P11157 (Mus musculus)
Explore P11157 
Go to UniProtKB:  P11157
IMPC:  MGI:98181
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP11157
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.40 Å
  • R-Value Free: 0.297 
  • R-Value Work: 0.218 
  • R-Value Observed: 0.218 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 75.1α = 90
b = 106.86β = 90
c = 91.46γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

Currently 1H0N does not have a validation slider image.

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-07-25
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2023-12-13
    Changes: Data collection, Database references, Derived calculations, Other, Refinement description