4N82

X-ray crystal structure of Streptococcus sanguinis NrdIox


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.88 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.208 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.4 of the entry. See complete history


Literature

Streptococcus sanguinis Class Ib Ribonucleotide Reductase: HIGH ACTIVITY WITH BOTH IRON AND MANGANESE COFACTORS AND STRUCTURAL INSIGHTS.

Makhlynets, O.Boal, A.K.Rhodes, D.V.Kitten, T.Rosenzweig, A.C.Stubbe, J.

(2014) J Biol Chem 289: 6259-6272

  • DOI: https://doi.org/10.1074/jbc.M113.533554
  • Primary Citation of Related Structures:  
    4N82, 4N83

  • PubMed Abstract: 

    Streptococcus sanguinis is a causative agent of infective endocarditis. Deletion of SsaB, a manganese transporter, drastically reduces S. sanguinis virulence. Many pathogenic organisms require class Ib ribonucleotide reductase (RNR) to catalyze the conversion of nucleotides to deoxynucleotides under aerobic conditions, and recent studies demonstrate that this enzyme uses a dimanganese-tyrosyl radical (Mn(III)2-Y(•)) cofactor in vivo. The proteins required for S. sanguinis ribonucleotide reduction (NrdE and NrdF, α and β subunits of RNR; NrdH and TrxR, a glutaredoxin-like thioredoxin and a thioredoxin reductase; and NrdI, a flavodoxin essential for assembly of the RNR metallo-cofactor) have been identified and characterized. Apo-NrdF with Fe(II) and O2 can self-assemble a diferric-tyrosyl radical (Fe(III)2-Y(•)) cofactor (1.2 Y(•)/β2) and with the help of NrdI can assemble a Mn(III)2-Y(•) cofactor (0.9 Y(•)/β2). The activity of RNR with its endogenous reductants, NrdH and TrxR, is 5,000 and 1,500 units/mg for the Mn- and Fe-NrdFs (Fe-loaded NrdF), respectively. X-ray structures of S. sanguinis NrdIox and Mn(II)2-NrdF are reported and provide a possible rationale for the weak affinity (2.9 μM) between them. These streptococcal proteins form a structurally distinct subclass relative to other Ib proteins with unique features likely important in cluster assembly, including a long and negatively charged loop near the NrdI flavin and a bulky residue (Thr) at a constriction in the oxidant channel to the NrdI interface. These studies set the stage for identifying the active form of S. sanguinis class Ib RNR in an animal model for infective endocarditis and establishing whether the manganese requirement for pathogenesis is associated with RNR.


  • Organizational Affiliation

    From the Departments of Chemistry and.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Ribonucleotide reductaseA [auth B],
B [auth A]
178Streptococcus sanguinis SK36Mutation(s): 0 
Gene Names: nrdISSA_2263
UniProt
Find proteins for A3CR20 (Streptococcus sanguinis (strain SK36))
Explore A3CR20 
Go to UniProtKB:  A3CR20
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA3CR20
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.88 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.208 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.726α = 90
b = 56.612β = 106.13
c = 73.387γ = 90
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction
DENZOdata reduction

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-01-08
    Type: Initial release
  • Version 1.1: 2014-02-26
    Changes: Database references
  • Version 1.2: 2014-03-19
    Changes: Database references
  • Version 1.3: 2017-11-15
    Changes: Refinement description
  • Version 1.4: 2023-09-20
    Changes: Data collection, Database references, Derived calculations, Refinement description