Crystal structure of the major celery allergen Api G 1

Experimental Data Snapshot

  • Resolution: 2.90 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.224 

wwPDB Validation   3D Report Full Report

This is version 1.3 of the entry. See complete history


Crystal Structure of the Major Celery Allergen Api G 1: Molecular Analysis of Cross-Reactivity.

Schirmer, T.Hoffmann-Somergrube, K.Susani, M.Breiteneder, H.Markovic-Housley, Z.

(2005) J Mol Biol 351: 1101

  • DOI: https://doi.org/10.1016/j.jmb.2005.06.054
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Many patients who have been sensitised to pollen, display allergic symptoms after ingestion of certain plant food such as fresh fruit, vegetables and nuts. The cause is the cross-reactivity between structurally very similar major plant allergens. In particular, allergy to celery is very frequently associated with birch and mugwort pollen sensitization, known as to the birch-mugwort-celery syndrome. The crystal structure of the major celery allergen Api g 1, a homologue of the major birch pollen allergen Bet v 1, has been determined to a resolution of 2.9 A. The structure of Api g 1 is very similar to that of Bet v 1 with major differences occurring in the segment comprised of residues 23-45, preceding the well conserved glycine-rich P-loop, as well as in loops beta3-beta4 and beta5-beta6. In particular, Api g 1 lacks E45, which has been shown to be a crucial residue for antibody recognition in the crystal complex of Bet v 1 with the Fab fragment of a murine monoclonal IgG (BV16) antibody. The absence of E45 and the structural differences in the preceding segment suggest that this region of the Api g 1 surface is probably not responsible for the observed cross-reactivity with Bet v 1. A detailed analysis of the molecular surface in combination with sequence alignment revealed three conserved surface patches which may account for cross-reactivity with Bet v 1. Several residues of Bet v 1 which have been shown by mutagenesis studies to be involved in IgE recognition belong to these conserved surface regions. The structure of Api g 1 and the related epitope analysis provides a molecular basis for a better understanding of allergen cross-reactivity and may lead to the development of hypoallergens which would allow a safer immunotherapy.

  • Organizational Affiliation

    Department of Structural Biology, Biozentrum, University of Basel, CH-4056 Basel, Switzerland.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B
154Apium graveolensMutation(s): 0 
Find proteins for P49372 (Apium graveolens)
Explore P49372 
Go to UniProtKB:  P49372
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP49372
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.90 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.224 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.878α = 90
b = 67.947β = 91.18
c = 48.001γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2005-06-13
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.2: 2019-03-06
    Changes: Advisory, Data collection, Experimental preparation, Other, Structure summary
  • Version 1.3: 2023-12-13
    Changes: Advisory, Data collection, Database references, Other, Refinement description