3G06

The Salmonella Virulence Effector SspH2 Functions As A Novel E3 Ligase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

A family of Salmonella virulence factors functions as a distinct class of autoregulated E3 ubiquitin ligases.

Quezada, C.M.Hicks, S.W.Galan, J.E.Stebbins, C.E.

(2009) Proc.Natl.Acad.Sci.USA 106: 4864-4869

  • DOI: 10.1073/pnas.0811058106

  • PubMed Abstract: 
  • Processes as diverse as receptor binding and signaling, cytoskeletal dynamics, and programmed cell death are manipulated by mimics of host proteins encoded by pathogenic bacteria. We show here that the Salmonella virulence factor SspH2 belongs to a g ...

    Processes as diverse as receptor binding and signaling, cytoskeletal dynamics, and programmed cell death are manipulated by mimics of host proteins encoded by pathogenic bacteria. We show here that the Salmonella virulence factor SspH2 belongs to a growing class of bacterial effector proteins that harness and subvert the eukaryotic ubiquitination pathway. This virulence protein possesses ubiquitination activity that depends on a conserved cysteine residue. A crystal structure of SspH2 reveals a canonical leucine-rich repeat (LRR) domain that interacts with a unique E3 ligase [which we have termed NEL for Novel E3 Ligase] C-terminal fold unrelated to previously observed HECT or RING-finger E3 ligases. Moreover, the LRR domain sequesters the catalytic cysteine residue contained in the NEL domain, and we suggest a mechanism for activation of the ligase requiring a substantial conformational change to release the catalytic domain for function. We also show that the N-terminal domain targets SspH2 to the apical plasma membrane of polarized epithelial cells and propose a model whereby binding of the LRR to proteins at the target site releases the ligase domain for site-specific function.


    Organizational Affiliation

    Laboratory of Structural Microbiology, The Rockefeller University, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SspH2 (Leucine-rich repeat protein)
A
622Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)Mutation(s): 0 
Gene Names: sspH2
EC: 2.3.2.27
Find proteins for P0CE12 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P0CE12
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.219 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 76.885α = 90.00
b = 76.885β = 90.00
c = 281.054γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
HKL-2000data reduction
REFMACrefinement
PHASERphasing
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-04-07
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance