3L4R | pdb_00003l4r

Crystal structure of the dog lipocalin allergen Can f 2 and implications for cross-reactivity to the cat allergen Fel d 4

• PDB DOI: https://doi.org/10.2210/pdb3L4R/pdb

• Classification: ALLERGEN, LIPID BINDING PROTEIN
• Organism(s): Canis lupus familiaris
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2009-12-21 Released: 2010-05-26 
• Deposition Author(s): Madhurantakam, C., Nilsson, O.B., Gronlund, H., Achour, A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.45 Å
• R-Value Free: 
  0.168 (Depositor), 0.180 (DCC) 
• R-Value Work: 
  0.157 (Depositor), 0.164 (DCC) 
• R-Value Observed: 
  0.158 (Depositor) 

Starting Model: experimental

Literature

Crystal Structure of the Dog Lipocalin Allergen Can f 2: Implications for Cross-reactivity to the Cat Allergen Fel d 4

Madhurantakam, C., Nilsson, O.B., Uchtenhagen, H., Konradsen, J., Saarne, T., Hogbom, E., Sandalova, T., Gronlund, H., Achour, A.

(2010) J Mol Biology 401: 68-83

• PubMed: 20621650 
• DOI: https://doi.org/10.1016/j.jmb.2010.05.043
• Primary Citation Related Structures: 
  3L4R


• PubMed Abstract: 
  

  The dog lipocalin allergen Can f 2 is an important cause of allergic sensitization in humans worldwide. Here, the first crystal structure of recombinant rCan f 2 at 1.45 A resolution displays a classical lipocalin fold with a conserved Gly-Xaa-Trp motif, in which Trp19 stabilizes the overall topology of the monomeric rCan f 2. Phe38 and Tyr84 localized on the L1 and L5 loops, respectively, control access to the highly hydrophobic calyx. Although the rCan f 2 calyx is nearly identical with the aero-allergens MUP1, Equ c 1 and A2U from mouse, horse and rat, respectively, no IgE cross-reactivity was found using sera from five mono-sensitized subjects. However, clear IgE cross-reactivity was demonstrated between Can f 2 and the cat allergen Fel d 4, although they share less than 22% sequence identity. This suggests a role for these allergens in co-sensitization between cat- and dog-allergic patients.

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Organizational Affiliation: 
• Centre for Infectious Medicine, F59, Department of Medicine Huddinge, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden.

Biological Assembly 1  

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

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

Macromolecule Content 

• Total Structure Weight: 19.57 kDa 
• Atom Count: 1,383 
• Modeled Residue Count: 151 
• Deposited Residue Count: 170 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Minor allergen Can f 2	A	170	Canis lupus familiaris	Mutation(s): 0  Gene Names: can f 2
UniProt
Find proteins for O18874 (Canis lupus familiaris) Explore O18874  Go to UniProtKB:  O18874

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	B [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.45 Å
• R-Value Free:  0.168 (Depositor), 0.180 (DCC) 
• R-Value Work:  0.157 (Depositor), 0.164 (DCC) 
• R-Value Observed: 0.158 (Depositor) 

Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 68.175	α = 90
b = 76.898	β = 90
c = 64.996	γ = 90

Software Package:

Software Name	Purpose
ADSC	data collection
PHASER	phasing
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2010-05-26 
Deposition Author(s): Madhurantakam, C., Nilsson, O.B., Gronlund, H., Achour, A.

Revision History  

• Version 1.0: 2010-05-26
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2023-11-01
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.3: 2024-11-20
  Changes: Structure summary