4FE7

structure of xylose-binding transcription activator xylR


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structures of the Escherichia coli transcription activator and regulator of diauxie, XylR: an AraC DNA-binding family member with a LacI/GalR ligand-binding domain.

Ni, L.Tonthat, N.K.Chinnam, N.Schumacher, M.A.

(2013) Nucleic Acids Res. 41: 1998-2008

  • DOI: 10.1093/nar/gks1207
  • Primary Citation of Related Structures:  4FE4

  • PubMed Abstract: 
  • Escherichia coli can rapidly switch to the metabolism of l-arabinose and d-xylose in the absence of its preferred carbon source, glucose, in a process called carbon catabolite repression. Transcription of the genes required for l-arabinose and d-xylo ...

    Escherichia coli can rapidly switch to the metabolism of l-arabinose and d-xylose in the absence of its preferred carbon source, glucose, in a process called carbon catabolite repression. Transcription of the genes required for l-arabinose and d-xylose consumption is regulated by the sugar-responsive transcription factors, AraC and XylR. E. coli represents a promising candidate for biofuel production through the metabolism of hemicellulose, which is composed of d-xylose and l-arabinose. Understanding the l-arabinose/d-xylose regulatory network is key for such biocatalyst development. Unlike AraC, which is a well-studied protein, little is known about XylR. To gain insight into XylR function, we performed biochemical and structural studies. XylR contains a C-terminal AraC-like domain. However, its N-terminal d-xylose-binding domain contains a periplasmic-binding protein (PBP) fold with structural homology to LacI/GalR transcription regulators. Like LacI/GalR proteins, the XylR PBP domain mediates dimerization. However, unlike LacI/GalR proteins, which dimerize in a parallel, side-to-side manner, XylR PBP dimers are antiparallel. Strikingly, d-xylose binding to this domain results in a helix to strand transition at the dimer interface that reorients both DNA-binding domains, allowing them to bind and loop distant operator sites. Thus, the combined data reveal the ligand-induced activation mechanism of a new family of DNA-binding proteins.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Xylose operon regulatory protein
A
412Escherichia coli (strain K12)Gene Names: xylR
Find proteins for P0ACI3 (Escherichia coli (strain K12))
Go to UniProtKB:  P0ACI3
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
XYS
Query on XYS

Download SDF File 
Download CCD File 
A
XYLOPYRANOSE
C5 H10 O5
SRBFZHDQGSBBOR-LECHCGJUSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.219 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 70.071α = 90.00
b = 70.071β = 90.00
c = 215.403γ = 90.00
Software Package:
Software NamePurpose
Blu-Icedata collection
MOSFLMdata reduction
SOLVEphasing
SCALEPACKdata scaling
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-12-12
    Type: Initial release
  • Version 1.1: 2013-01-02
    Type: Database references
  • Version 1.2: 2013-02-20
    Type: Database references
  • Version 1.3: 2017-11-15
    Type: Refinement description