Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 16.61 kDa 
• Atom Count: 1258 
• Residue Count: 140 
• Unique protein chains: 1

3F3X

Crystal structure of the transcriptional regulator BldR from Sulfolobus Solfataricus

• DOI: 10.2210/pdb3F3X/pdb

• Classification: TRANSCRIPTION
• Organism(s): Saccharolobus solfataricus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2008-10-31 Released: 2009-05-05 
• Deposition Author(s): Di Fiore, A., De Simone, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.230 
• R-Value Work: 0.201 

Literature

Structural analysis of BldR from Sulfolobus solfataricus provides insights into the molecular basis of transcriptional activation in archaea by MarR family proteins.

Di Fiore, A., Fiorentino, G., Vitale, R.M., Ronca, R., Amodeo, P., Pedone, C., Bartolucci, S., De Simone, G.

(2009) J Mol Biol 388: 559-569

• PubMed: 19298823 
• DOI: 10.1016/j.jmb.2009.03.030
• Primary Citation of Related Structures:  
  3F3X


• PubMed Abstract: 
  

The multiple antibiotic resistance regulator (MarR) family constitutes a significant class of transcriptional regulators whose members control a variety of important biological functions such as regulation of response to environmental stress, control of virulence factor production, resistance to antimicrobial agents, and regulation of aromatic catabolic pathways. Although the majority of MarR family members have been characterized as transcriptional repressors, a few examples of transcriptional activators have also been reported. BldR is a newly identified member of this family that has been demonstrated to act as a transcriptional activator in stress response to aromatic compounds in the crenarchaeon Sulfolobus solfataricus. In this work, we report findings on the BldR X-ray crystal structure and present a molecular modeling study on the complex that this protein forms with its cognate DNA sequence, thus providing the first detailed description of the DNA-binding mechanism of an archaeal activator belonging to the MarR family. Two residues responsible for the high binding specificity of this transcriptional regulator were also identified. Our studies demonstrated that, in Archaea, the capability of MarR family members to act as activators or repressors is not related to a particular DNA-binding mechanism but rather could be due to the position of the binding site on the target DNA. Moreover, since genes encoding MarR proteins often control transcription of operons that encode for multisubstrate efflux pumps, our results also provided important insights for the identification of new tools to overcome the microorganism's multidrug resistance.

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Organizational Affiliation: 

Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, Naples, Italy.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transcriptional regulator, marR family, putative	A	144	Saccharolobus solfataricus	Mutation(s): 0  Gene Names: SSO1352
Find proteins for Q97YG9 (Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2)) Explore Q97YG9  Go to UniProtKB:  Q97YG9

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	A	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.230 
• R-Value Work: 0.201 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 86.11	α = 90
b = 86.11	β = 90
c = 43.24	γ = 90

Software Package:

Software Name	Purpose
MAR345	data collection
SOLVE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2008-10-31 
• Released Date: 2009-05-05 
Deposition Author(s): Di Fiore, A., De Simone, G.

Revision History 

• Version 1.0: 2009-05-05
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2017-10-25
  Changes: Refinement description