3C01

Crystal structural of native SpaS C-terminal domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural analysis of the essential self-cleaving type III secretion proteins EscU and SpaS.

Zarivach, R.Deng, W.Vuckovic, M.Felise, H.B.Nguyen, H.V.Miller, S.I.Finlay, B.B.Strynadka, N.C.

(2008) Nature 453: 124-127

  • DOI: 10.1038/nature06832
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • During infection by Gram-negative pathogenic bacteria, the type III secretion system (T3SS) is assembled to allow for the direct transmission of bacterial virulence effectors into the host cell. The T3SS system is characterized by a series of promine ...

    During infection by Gram-negative pathogenic bacteria, the type III secretion system (T3SS) is assembled to allow for the direct transmission of bacterial virulence effectors into the host cell. The T3SS system is characterized by a series of prominent multi-component rings in the inner and outer bacterial membranes, as well as a translocation pore in the host cell membrane. These are all connected by a series of polymerized tubes that act as the direct conduit for the T3SS proteins to pass through to the host cell. During assembly of the T3SS, as well as the evolutionarily related flagellar apparatus, a post-translational cleavage event within the inner membrane proteins EscU/FlhB is required to promote a secretion-competent state. These proteins have long been proposed to act as a part of a molecular switch, which would regulate the appropriate chronological secretion of the various T3SS apparatus components during assembly and subsequently the transported virulence effectors. Here we show that a surface type II beta-turn in the Escherichia coli protein EscU undergoes auto-cleavage by a mechanism involving cyclization of a strictly conserved asparagine residue. Structural and in vivo analysis of point and deletion mutations illustrates the subtle conformational effects of auto-cleavage in modulating the molecular features of a highly conserved surface region of EscU, a potential point of interaction with other T3SS components at the inner membrane. In addition, this work provides new structural insight into the distinct conformational requirements for a large class of self-cleaving reactions involving asparagine cyclization.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Surface presentation of antigens protein spaS
A, B, C, D
48Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)Mutation(s): 0 
Gene Names: spaS
Find proteins for P40702 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P40702
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Surface presentation of antigens protein spaS
E, F, G, H
98Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)Mutation(s): 0 
Gene Names: spaS
Find proteins for P40702 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P40702
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
E, F, G, H
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
MPD
Query on MPD

Download SDF File 
Download CCD File 
G
(4S)-2-METHYL-2,4-PENTANEDIOL
C6 H14 O2
SVTBMSDMJJWYQN-YFKPBYRVSA-N
 Ligand Interaction
CYS
Query on CYS

Download SDF File 
Download CCD File 
E, F, G, H
CYSTEINE
C3 H7 N O2 S
XUJNEKJLAYXESH-REOHCLBHSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.223 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 96.663α = 90.00
b = 96.663β = 90.00
c = 217.511γ = 120.00
Software Package:
Software NamePurpose
HKL-2000data reduction
HKL-2000data scaling
DENZOdata reduction
PHASERphasing
REFMACrefinement
SCALEPACKdata scaling
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-04-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description