3HO6

Structure-function analysis of inositol hexakisphosphate-induced autoprocessing in clostridium difficile toxin A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.165 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure-function analysis of inositol hexakisphosphate-induced autoprocessing in Clostridium difficile toxin A.

Pruitt, R.N.Chagot, B.Cover, M.Chazin, W.J.Spiller, B.Lacy, D.B.

(2009) J.Biol.Chem. 284: 21934-21940

  • DOI: 10.1074/jbc.M109.018929

  • PubMed Abstract: 
  • The action of Clostridium difficile toxins A and B depends on inactivation of host small G-proteins by glucosylation. Cellular inositol hexakisphosphate (InsP6) induces an autocatalytic cleavage of the toxins, releasing an N-terminal glucosyltransfer ...

    The action of Clostridium difficile toxins A and B depends on inactivation of host small G-proteins by glucosylation. Cellular inositol hexakisphosphate (InsP6) induces an autocatalytic cleavage of the toxins, releasing an N-terminal glucosyltransferase domain into the host cell cytosol. We have defined the cysteine protease domain (CPD) responsible for autoprocessing within toxin A (TcdA) and report the 1.6 A x-ray crystal structure of the domain bound to InsP6. InsP6 is bound in a highly basic pocket that is separated from an unusual active site by a beta-flap structure. Functional studies confirm an intramolecular mechanism of cleavage and highlight specific residues required for InsP6-induced TcdA processing. Analysis of the structural and functional data in the context of sequences from similar and diverse origins highlights a C-terminal extension and a pi-cation interaction within the beta-flap that appear to be unique among the large clostridial cytotoxins.


    Organizational Affiliation

    Department of Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232-2363, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Toxin A
A, B
267Clostridioides difficileMutation(s): 0 
Gene Names: toxA (tcdA)
EC: 3.4.22.-
Find proteins for P16154 (Clostridioides difficile)
Go to UniProtKB:  P16154
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
IHP
Query on IHP

Download SDF File 
Download CCD File 
A, B
INOSITOL HEXAKISPHOSPHATE
C6 H18 O24 P6
IMQLKJBTEOYOSI-GPIVLXJGSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.165 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 141.312α = 90.00
b = 43.500β = 112.88
c = 94.692γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
SHARPphasing
HKL-2000data scaling
HKL-2000data collection
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-06-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance