Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Homo 8-mer - A8 

Biological assembly 1 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 125.73 kDa 
• Atom Count: 8247 
• Residue Count: 1028 
• Unique protein chains: 1

4PHX

Crystal structure of AggB, the minor subunit of aggregative adherence fimbriae type I from the Escherichia coli O4H104

• DOI: 10.2210/pdb4PHX/pdb

• Classification: CELL ADHESION
• Organism(s): Escherichia coli
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2014-05-07 Released: 2014-10-01 
• Deposition Author(s): Pakharukova, N.A., Tuitilla, M., Zavialov, A.V.
• Funding Organization(s): Academy of Finland, Erasmus Mundus

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.273 
• R-Value Work: 0.228 
• R-Value Observed: 0.230 

Literature

Structural Insight into Host Recognition by Aggregative Adherence Fimbriae of Enteroaggregative Escherichia coli.

Berry, A.A., Yang, Y., Pakharukova, N., Garnett, J.A., Lee, W.C., Cota, E., Marchant, J., Roy, S., Tuittila, M., Liu, B., Inman, K.G., Ruiz-Perez, F., Mandomando, I., Nataro, J.P., Zavialov, A.V., Matthews, S.

(2014) PLoS Pathog 10: e1004404-e1004404

• PubMed: 25232738 
• DOI: 10.1371/journal.ppat.1004404
• Primary Citation of Related Structures:  
  4PH8, 4PHX, 4OR1, 2MPV


• PubMed Abstract: 
  

Enteroaggregative Escherichia coli (EAEC) is a leading cause of acute and persistent diarrhea worldwide. A recently emerged Shiga-toxin-producing strain of EAEC resulted in significant mortality and morbidity due to progressive development of hemolytic-uremic syndrome. The attachment of EAEC to the human intestinal mucosa is mediated by aggregative adherence fimbria (AAF). Using X-ray crystallography and NMR structures, we present new atomic resolution insight into the structure of AAF variant I from the strain that caused the deadly outbreak in Germany in 2011, and AAF variant II from archetype strain 042, and propose a mechanism for AAF-mediated adhesion and biofilm formation. Our work shows that major subunits of AAF assemble into linear polymers by donor strand complementation where a single minor subunit is inserted at the tip of the polymer by accepting the donor strand from the terminal major subunit. Whereas the minor subunits of AAF have a distinct conserved structure, AAF major subunits display large structural differences, affecting the overall pilus architecture. These structures suggest a mechanism for AAF-mediated adhesion and biofilm formation. Binding experiments using wild type and mutant subunits (NMR and SPR) and bacteria (ELISA) revealed that despite the structural differences AAF recognize a common receptor, fibronectin, by employing clusters of basic residues at the junction between subunits in the pilus. We show that AAF-fibronectin attachment is based primarily on electrostatic interactions, a mechanism not reported previously for bacterial adhesion to biotic surfaces.

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Organizational Affiliation: 

Centre for Structural Biology, Department of Life Sciences, Imperial College London, South Kensington, London, United Kingdom.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein AggB	A, B, C, D, E, F, G, H	142	Escherichia coli	Mutation(s): 0  Gene Names: aggB
Find proteins for P46006 (Escherichia coli) Explore P46006  Go to UniProtKB:  P46006

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.273 
• R-Value Work: 0.228 
• R-Value Observed: 0.230 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 130.797	α = 90
b = 163.968	β = 90
c = 58.627	γ = 90

Software Package:

Software Name	Purpose
SCALA	data scaling
PDB_EXTRACT	data extraction
PHASER	phasing
PHENIX	refinement

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2014-05-07 
• Released Date: 2014-10-01 
Deposition Author(s): Pakharukova, N.A., Tuitilla, M., Zavialov, A.V.

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Funding Organization	Location	Grant Number
Academy of Finland	Finland	FA-136333
Academy of Finland	Finland	FA-140959
Erasmus Mundus	Finland	TRIPLEI2011311

Revision History 

• Version 1.0: 2014-10-01
  Type: Initial release
  
• Version 1.1: 2019-02-20
  Changes: Advisory, Data collection, Derived calculations