5BS6

Apo structure of transcriptional factor AraR from Bacteroides thetaiotaomicron VPI


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.195 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

A novel transcriptional regulator of L-arabinose utilization in human gut bacteria.

Chang, C.Tesar, C.Li, X.Kim, Y.Rodionov, D.A.Joachimiak, A.

(2015) Nucleic Acids Res 43: 10546-10559

  • DOI: 10.1093/nar/gkv1005
  • Primary Citation of Related Structures:  
    5BS6, 5DD4, 5DDG, 5DEQ

  • PubMed Abstract: 
  • Carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown ...

    Carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown. By a combination of bioinformatics and experimental approaches, we have identified an NrtR family transcription factor (BT0354 in B. thetaiotaomicron, BtAraR) as a novel regulator controlling the arabinose utilization genes. L-arabinose was confirmed to be a negative effector of BtAraR. We have solved the crystal structures of the apo and L-arabinose-bound BtAraR proteins, as well as the complex of apo-protein with a specific DNA operator. BtAraR forms a homodimer with each subunit comprised of the ligand-binding Nudix hydrolase-like domain and the DNA-binding winged-helix-turn-helix (wHTH) domain. We have identified the residues involved in binding of L-arabinose and recognition of DNA. The majority of these residues are well conserved in the AraR orthologs in Bacteroidetes. In the structure of the BtAraR-DNA complex, we found the unique interaction of arginine intercalating its guanidinum moiety into the base pair stacking of B-DNA. L-arabinose binding induces movement of wHTH domains, resulting in a conformation unsuitable for DNA binding. Our analysis facilitates reconstruction of the metabolic and regulatory networks involved in carbohydrate utilization in human gut Bacteroides.


    Organizational Affiliation

    Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA andrzejj@anl.gov.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
transcriptional regulator AraRA, B, C, D228Bacteroides thetaiotaomicron VPI-5482Mutation(s): 0 
Gene Names: BT_0354
UniProt
Find proteins for Q8AAV8 (Bacteroides thetaiotaomicron (strain ATCC 29148 / DSM 2079 / NCTC 10582 / E50 / VPI-5482))
Explore Q8AAV8 
Go to UniProtKB:  Q8AAV8
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download Ideal Coordinates CCD File 
E [auth A], F [auth B], G [auth C], H [auth D]1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, DL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.195 
  • R-Value Observed: 0.197 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 176.437α = 90
b = 176.437β = 90
c = 118.426γ = 120
Software Package:
Software NamePurpose
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
HKL-2000data reduction
HKL-3000phasing
SBC-Collectdata collection

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-06-17
    Type: Initial release
  • Version 1.1: 2015-06-24
    Changes: Other
  • Version 1.2: 2015-10-21
    Changes: Database references
  • Version 1.3: 2015-12-16
    Changes: Database references