6FQ4

Structure of Chlamydial virulence factor TarP and vinculin head domain

• PDB DOI: https://doi.org/10.2210/pdb6FQ4/pdb

• Classification: CELL ADHESION
• Organism(s): Gallus gallus, Chlamydia caviae
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2018-02-13 Released: 2018-05-09 
• Deposition Author(s): Whitewood, A.J., Singh, A.K., Brown, D.G., Goult, B.T.
• Funding Organization(s): Biotechnology and Biological Sciences Research Council, Human Frontier Science Program (HFSP)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.89 Å
• R-Value Free: 0.346 
• R-Value Work: 0.286 
• R-Value Observed: 0.289 

Literature

Chlamydial virulence factor TarP mimics talin to disrupt the talin-vinculin complex.

Whitewood, A.J., Singh, A.K., Brown, D.G., Goult, B.T.

(2018) FEBS Lett 592: 1751-1760

• PubMed: 29710402 
• DOI: https://doi.org/10.1002/1873-3468.13074
• Primary Citation of Related Structures:  
  6FQ4


• PubMed Abstract: 
  

  Vinculin is a central component of mechanosensitive adhesive complexes that form between cells and the extracellular matrix. A myriad of infectious agents mimic vinculin binding sites (VBS), enabling them to hijack the adhesion machinery and facilitate cellular entry. Here, we report the structural and biochemical characterisation of VBS from the chlamydial virulence factor TarP. Whilst the affinities of isolated VBS peptides from TarP and talin for vinculin are similar, their behaviour in larger fragments is markedly different. In talin, VBS are cryptic and require mechanical activation to bind vinculin, whereas the TarP VBS are located in disordered regions, and so are constitutively active. We demonstrate that the TarP VBS can uncouple talin:vinculin complexes, which may lead to adhesion destabilisation.

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Organizational Affiliation: 

School of Biosciences, University of Kent, Canterbury, UK.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 33.51 kDa 
• Atom Count: 2,085 
• Modelled Residue Count: 268 
• Deposited Residue Count: 300 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Vinculin	A	280	Gallus gallus	Mutation(s): 0  Gene Names: VCL, VINC1
UniProt
Find proteins for P12003 (Gallus gallus) Explore P12003  Go to UniProtKB:  P12003

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
TarP-VBS1	B	20	Chlamydia caviae	Mutation(s): 0
UniProt
Find proteins for Q824H6 (Chlamydia caviae (strain ATCC VR-813 / DSM 19441 / 03DC25 / GPIC)) Explore Q824H6  Go to UniProtKB:  Q824H6

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.89 Å
• R-Value Free: 0.346 
• R-Value Work: 0.286 
• R-Value Observed: 0.289 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 51.807	α = 90
b = 66.873	β = 90
c = 95.832	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
Aimless	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2018-05-09 
Deposition Author(s): Whitewood, A.J., Singh, A.K., Brown, D.G., Goult, B.T.

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Funding Organization	Location	Grant Number
Biotechnology and Biological Sciences Research Council	United Kingdom	BB/N007336/1
Human Frontier Science Program (HFSP)		RGP00001/2016

Revision History  

• Version 1.0: 2018-05-09
  Type: Initial release
  
• Version 1.1: 2018-06-13
  Changes: Data collection, Database references
• Version 1.2: 2024-01-17
  Changes: Data collection, Database references, Refinement description