Biological Assembly 1  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 18.75 kDa 
• Atom Count: 1396 
• Modelled Residue Count: 159 
• Deposited Residue Count: 159 
• Unique protein chains: 1

1EW3

CRYSTAL STRUCTURE OF THE MAJOR HORSE ALLERGEN EQU C 1

• DOI: 10.2210/pdb1EW3/pdb

• Classification: ALLERGEN
• Organism(s): Equus caballus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2000-04-21 Released: 2000-05-03 
• Deposition Author(s): Lascombe, M.B., Gregoire, C., Poncet, P., Tavares, G.A., Rosinski-Chupin, I., Rabillon, J., Goubran-Botros, H., Mazie, J.C., David, B., Alzari, P.M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.252 
• R-Value Work: 0.195 

Literature

Crystal structure of the allergen Equ c 1. A dimeric lipocalin with restricted IgE-reactive epitopes.

Lascombe, M.B., Gregoire, C., Poncet, P., Tavares, G.A., Rosinski-Chupin, I., Rabillon, J., Goubran-Botros, H., Mazie, J.C., David, B., Alzari, P.M.

(2000) J Biol Chem 275: 21572-21577

• PubMed: 10787420 
• DOI: 10.1074/jbc.M002854200
• Primary Citation of Related Structures:  
  1EW3


• PubMed Abstract: 
  

The three-dimensional structure of the major horse allergen Equ c 1 has been determined at 2.3 A resolution by x-ray crystallography. Equ c 1 displays the typical fold of lipocalins, a beta-barrel flanked by a C-terminal alpha-helix. The space between the two beta-sheets of the barrel defines an internal cavity that could serve, as in other lipocalins, for the binding and transport of small hydrophobic ligands. Equ c 1 crystallizes in a novel dimeric form, which is distinct from that observed in other lipocalin dimers and corresponds to the functional form of the allergen. Binding studies of point mutants of the allergen with specific monoclonal antibodies raised in mouse and IgE serum from horse allergic patients allowed to identify putative B cell antigenic determinants. In addition, total inhibition of IgE serum recognition by a single specific monoclonal antibody revealed the restricted nature of the IgE binding target on the molecular surface of Equ c 1.

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Related Citations: 

• Crystallization and Preliminary Crystallographic Analysis of the Major Horse Allergen Equ c 1
  Gregoire, C., Tavares, G.A., Lorenzo, H.K., Dandeu, J.P., David, B., Alzari, P.M.
  (1999) Acta Crystallogr D Biol Crystallogr 55: 880

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Organizational Affiliation: 

Unité de Biochimie Structurale (CNRS URA 2185), Unité d'Immuno-Allergie, 25 et 28 rue du Docteur Roux, 75724 Paris Cedex 15, France.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ALLERGEN EQU C 1	A	159	Equus caballus	Mutation(s): 0
Find proteins for Q95182 (Equus caballus) Explore Q95182  Go to UniProtKB:  Q95182

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.252 
• R-Value Work: 0.195 
• Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 84.04	α = 90
b = 84.04	β = 90
c = 58.48	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing
REFMAC	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2000-04-21 
• Released Date: 2000-05-03 
Deposition Author(s): Lascombe, M.B., Gregoire, C., Poncet, P., Tavares, G.A., Rosinski-Chupin, I., Rabillon, J., Goubran-Botros, H., Mazie, J.C., David, B., Alzari, P.M.

Revision History  

• Version 1.0: 2000-05-03
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance