4R6I

AtxA protein, a virulence regulator from Bacillus anthracis.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.65 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity.

Hammerstrom, T.G.Horton, L.B.Swick, M.C.Joachimiak, A.Osipiuk, J.Koehler, T.M.

(2015) Mol.Microbiol. 95: 426-441

  • DOI: 10.1111/mmi.12867

  • PubMed Abstract: 
  • The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthetic operon. AtxA activity is elevated during growth in media containing glucose and CO(2)/bicarbonate, and there is a positive corr ...

    The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthetic operon. AtxA activity is elevated during growth in media containing glucose and CO(2)/bicarbonate, and there is a positive correlation between the CO(2)/bicarbonate signal, AtxA activity and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His→Asp) and phosphoablative (His→Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (i) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (ii) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator, and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism.


    Organizational Affiliation

    Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Anthrax toxin expression trans-acting positive regulator
A, B
478Bacillus anthracisGene Names: atxA
Find proteins for Q44636 (Bacillus anthracis)
Go to UniProtKB:  Q44636
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
LMT
Query on LMT

Download SDF File 
Download CCD File 
A, B
DODECYL-BETA-D-MALTOSIDE
C24 H46 O11
NLEBIOOXCVAHBD-QKMCSOCLSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

Unit Cell:
Length (Å)Angle (°)
a = 130.460α = 90.00
b = 135.167β = 90.00
c = 180.908γ = 90.00
Software Package:
Software NamePurpose
HKL-3000data scaling
SBC-Collectdata collection
REFMACrefinement
PDB_EXTRACTdata extraction
PHENIXphasing
HKL-3000data reduction
SCALEPACKdata scaling
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-10-22
    Type: Initial release
  • Version 1.1: 2014-12-03
    Type: Database references
  • Version 1.2: 2015-02-11
    Type: Database references
  • Version 1.3: 2017-11-22
    Type: Refinement description