6NWM

Structures of the transcriptional regulator BgaR, a lactose sensor.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.11 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.204 
  • R-Value Observed: 0.205 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structures of the transcriptional regulator BgaR, a lactose sensor.

Newman, J.Caron, K.Nebl, T.Peat, T.S.

(2019) Acta Crystallogr D Struct Biol 75: 639-646

  • DOI: 10.1107/S2059798319008131
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The structure of BgaR, a transcriptional regulator of the lactose operon in Clostridium perfringens, has been solved by SAD phasing using a mercury derivative. BgaR is an exquisite sensor of lactose, with a binding affinity in the low-micromolar rang ...

    The structure of BgaR, a transcriptional regulator of the lactose operon in Clostridium perfringens, has been solved by SAD phasing using a mercury derivative. BgaR is an exquisite sensor of lactose, with a binding affinity in the low-micromolar range. This sensor and regulator has been captured bound to lactose and to lactulose as well as in a nominal apo form, and was compared with AraC, another saccharide-binding transcriptional regulator. It is shown that the saccharides bind in the N-terminal region of a jelly-roll fold, but that part of the saccharide is exposed to bulk solvent. This differs from the classical AraC saccharide-binding site, which is mostly sequestered from the bulk solvent. The structures of BgaR bound to lactose and to lactulose highlight how specific and nonspecific interactions lead to a higher binding affinity of BgaR for lactose compared with lactulose. Moreover, solving multiple structures of BgaR in different space groups, both bound to saccharides and unbound, verified that the dimer interface along a C-terminal helix is similar to the dimer interface observed in AraC.


    Organizational Affiliation

    Biomedical Program, CSIRO, 343 Royal Parade, Parkville, VIC 3052, Australia.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transcriptional regulator BgaR
A, B
182Clostridium perfringens str. 13Mutation(s): 0 
Gene Names: CPE0770
Find proteins for Q8XMB9 (Clostridium perfringens (strain 13 / Type A))
Go to UniProtKB:  Q8XMB9
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
W9T
Query on W9T

Download CCD File 
A, B
4-O-beta-D-galactopyranosyl-beta-D-fructofuranose
C12 H22 O11
JCQLYHFGKNRPGE-FCVZTGTOSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.11 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.204 
  • R-Value Observed: 0.205 
  • Space Group: P 2 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 46.439α = 90
b = 87.528β = 90
c = 118.974γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
Aimlessdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Deposited Date: 2019-02-06 
  • Released Date: 2019-07-17 
  • Deposition Author(s): Peat, T.S., Newman, J.

Revision History 

  • Version 1.0: 2019-07-17
    Type: Initial release
  • Version 1.1: 2019-07-24
    Changes: Data collection, Database references