3HRS

Crystal Structure of the Manganese-activated Repressor ScaR: apo form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.227 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Characterization and structure of the manganese-responsive transcriptional regulator ScaR.

Stoll, K.E.Draper, W.E.Kliegman, J.I.Golynskiy, M.V.Brew-Appiah, R.A.Phillips, R.K.Brown, H.K.Breyer, W.A.Jakubovics, N.S.Jenkinson, H.F.Brennan, R.G.Cohen, S.M.Glasfeld, A.

(2009) Biochemistry 48: 10308-10320

  • DOI: 10.1021/bi900980g
  • Primary Citation of Related Structures:  
    3HRU, 3HRS, 3HRT

  • PubMed Abstract: 
  • The streptococcal coaggregation regulator (ScaR) of Streptococcus gordonii is a manganese-dependent transcriptional regulator. When intracellular manganese concentrations become elevated, ScaR represses transcription of the scaCBA operon, which encodes a manganese uptake transporter ...

    The streptococcal coaggregation regulator (ScaR) of Streptococcus gordonii is a manganese-dependent transcriptional regulator. When intracellular manganese concentrations become elevated, ScaR represses transcription of the scaCBA operon, which encodes a manganese uptake transporter. A member of the DtxR/MntR family of metalloregulators, ScaR shares sequence similarity with other family members, and many metal-binding residues are conserved. Here, we show that ScaR is an active dimer, with two dimers binding the 46 base pair scaC operator. Each ScaR subunit binds two manganese ions, and the protein is activated by a variety of other metal ions, including Cd(2+), Co(2+), and Ni(2+) but not Zn(2+). The crystal structure of apo-ScaR reveals a tertiary and quaternary structure similar to its homologue, the iron-responsive regulator DtxR. While each DtxR subunit binds a metal ion in two sites, labeled primary and ancillary, crystal structures of ScaR determined in the presence of Cd(2+) and Zn(2+) show only a single occupied metal-binding site that is novel to ScaR. The site analogous to the primary site in DtxR is unoccupied, and the ancillary site is absent from ScaR. Instead, metal ions bind to ScaR at a site labeled "secondary", which is composed of Glu80, Cys123, His125, and Asp160 and lies roughly 5 A away from where the ancillary site would be predicted to exist. This difference suggests that ScaR and its closely related homologues are activated by a mechanism distinct from that of either DtxR or MntR.


    Organizational Affiliation

    Department of Chemistry, Reed College, Portland, Oregon 97202, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Metalloregulator ScaRA, B214Streptococcus gordoniiMutation(s): 0 
Gene Names: scaRmarRNCTC7870_01959UA00_01344
UniProt
Find proteins for Q9RFN3 (Streptococcus gordonii)
Explore Q9RFN3 
Go to UniProtKB:  Q9RFN3
Protein Feature View
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  • Reference Sequence
Small Molecules
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.227 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 70.6α = 90
b = 70.6β = 90
c = 301.5γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
SCALAdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
ADSCdata collection
SOLVEphasing
MOSFLMdata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-06-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2019-07-24
    Changes: Data collection, Refinement description