Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 23.58 kDa 
• Atom Count: 1633 
• Modelled Residue Count: 201 
• Deposited Residue Count: 215 
• Unique protein chains: 1

2FM9

Structure of Salmonella SipA residues 48-264

• PDB DOI: 10.2210/pdb2FM9/pdb

• Classification: CELL INVASION
• Organism(s): Salmonella enterica subsp. enterica serovar Typhimurium
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2006-01-08 Released: 2006-03-21 
• Deposition Author(s): Lilic, M., Vujanac, M., Stebbins, C.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.255 
• R-Value Work: 0.202 
• R-Value Observed: 0.204 

Literature

A common structural motif in the binding of virulence factors to bacterial secretion chaperones.

Lilic, M., Vujanac, M., Stebbins, C.E.

(2006) Mol Cell 21: 653-664

• PubMed: 16507363 
• DOI: 10.1016/j.molcel.2006.01.026
• Primary Citation of Related Structures:  
  2FM8, 2FM9


• PubMed Abstract: 
  

Salmonella invasion protein A (SipA) is translocated into host cells by a type III secretion system (T3SS) and comprises two regions: one domain binds its cognate type III secretion chaperone, InvB, in the bacterium to facilitate translocation, while a second domain functions in the host cell, contributing to bacterial uptake by polymerizing actin. We present here the crystal structures of the SipA chaperone binding domain (CBD) alone and in complex with InvB. The SipA CBD is found to consist of a nonglobular polypeptide as well as a large globular domain, both of which are necessary for binding to InvB. We also identify a structural motif that may direct virulence factors to their cognate chaperones in a diverse range of pathogenic bacteria. Disruption of this structural motif leads to a destabilization of several chaperone-substrate complexes from different species, as well as an impairment of secretion in Salmonella.

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Organizational Affiliation: 

Laboratory of Structural Microbiology, The Rockefeller University, New York, New York 10021, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Cell invasion protein sipA	A	215	Salmonella enterica subsp. enterica serovar Typhimurium	Mutation(s): 0  Gene Names: sipA, sspA
UniProt
Find proteins for P0CL52 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)) Explore P0CL52  Go to UniProtKB:  P0CL52

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.255 
• R-Value Work: 0.202 
• R-Value Observed: 0.204 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 71.08	α = 90
b = 71.08	β = 90
c = 95.439	γ = 120

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
REFMAC	refinement
PDB_EXTRACT	data extraction
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-01-08 
• Released Date: 2006-03-21 
Deposition Author(s): Lilic, M., Vujanac, M., Stebbins, C.E.

Revision History  

• Version 1.0: 2006-03-21
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Advisory, Version format compliance
• Version 1.3: 2017-10-18
  Changes: Refinement description