2YGU

Crystal structure of fire ant venom allergen, Sol I 2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.237 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of Sol I 2, a Major Allergen from Fire Ant Venom

Borer, A.S.Wassmann, P.Schmidt, M.Hoffman, D.R.Zhou, J.J.Wright, C.Schirmer, T.Markovic-Housley, Z.

(2012) J.Mol.Biol. 415: 635

  • DOI: 10.1016/j.jmb.2011.10.009

  • PubMed Abstract: 
  • Sol i 2 is a potent allergen from the venom of red imported fire ant, which contains allergens Sol i 1, Sol i 2, Sol i 3, and Sol i 4 that are known to be powerful triggers of anaphylaxis. Sol i 2 causes IgE antibody production in about one-third of ...

    Sol i 2 is a potent allergen from the venom of red imported fire ant, which contains allergens Sol i 1, Sol i 2, Sol i 3, and Sol i 4 that are known to be powerful triggers of anaphylaxis. Sol i 2 causes IgE antibody production in about one-third of individuals stung by fire ants. Baculovirus recombinant dimeric Sol i 2 was crystallized as a native and selenomethionyl-derivatized protein, and its structure has been determined by single-wavelength anomalous dispersion at 2.6 Å resolution. The overall fold of each subunit consists of five helices that enclose a central hydrophobic cavity. The structure is stabilized by three intramolecular disulfide bridges and one intermolecular disulfide bridge. The nearest structural homologue is the sequence-unrelated odorant binding protein and pheromone binding protein LUSH of the fruit fly Drosophila, which may suggest a similar biological function. To test this hypothesis, we measured the reversible binding of various pheromones, plant odorants, and other ligands to Sol i 2 by the changes in N-phenyl-1-naphthylamine fluorescence emission upon binding of ligands that compete with N-phenyl-1-naphthylamine. The highest binding affinity was observed for hydrophobic ligands such as aphid alarm pheromone (E)-β-farnesene, analogs of ant alarm pheromones, and plant volatiles decane, undecane, and β-caryophyllene. Conceivably, Sol i 2 may play a role in capturing and/or transporting small hydrophobic ligands such as pheromones, odors, fatty acids, or short-living hydrophobic primers. Molecular surface analysis, in combination with sequence alignment, can explain the serological cross-reactivity observed between some ant species.


    Organizational Affiliation

    Department of Structural Biology, Biozentrum, University of Basel, Basel, Switzerland.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
VENOM ALLERGEN 2
A, B, C, D, E, F, G, H
125Solenopsis invictaMutation(s): 0 
Find proteins for P35775 (Solenopsis invicta)
Go to UniProtKB:  P35775
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HP6
Query on HP6

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
HEPTANE
C7 H16
IMNFDUFMRHMDMM-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
HP6Kd: 322 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.237 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 110.211α = 90.00
b = 139.160β = 90.00
c = 62.093γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
SCALAdata scaling
SHELXphasing
MOSFLMdata reduction
REFMACrefinement
DMphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-11-23
    Type: Initial release
  • Version 1.1: 2011-12-21
    Type: Other
  • Version 1.2: 2012-02-01
    Type: Other