6HHE

Crystal structure of the medfly Odorant Binding Protein CcapOBP22/CcapOBP69a

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.52 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.194 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history. 


Literature

Structural and biochemical evaluation of Ceratitis capitata odorant-binding protein 22 affinity for odorants involved in intersex communication.

Falchetto, M., Ciossani, G., Scolari, F., Di Cosimo, A., Nenci, S., Field, L.M., Mattevi, A., Zhou, J.J., Gasperi, G., Forneris, F.

(2019) Insect Mol Biol 28: 431-443

  • DOI: 10.1111/imb.12559
  • Primary Citation of Related Structures:  
    6HHE

  • PubMed Abstract: 

    • In insects, odorant-binding proteins (OBPs) connect the peripheral sensory system to receptors of olfactory organs. Medfly Ceratitis capitata CcapObp22 shows 37% identity and close phylogenetic affinities with Drosophila melanogaster OBP69a/pheromone-bin ...

    In insects, odorant-binding proteins (OBPs) connect the peripheral sensory system to receptors of olfactory organs. Medfly Ceratitis capitata CcapObp22 shows 37% identity and close phylogenetic affinities with Drosophila melanogaster OBP69a/pheromone-binding protein related protein 1. The CcapObp22 gene is transcribed in the antennae and maxillary palps, suggesting an active role in olfaction. Here, we recombinantly produced CcapObp22, obtaining a 13.5 kDa protein capable of binding multiple strongly hydrophobic terpene compounds, including medfly male pheromone components. The highest binding affinity [half maximal effective concentration (EC50) = 0.48 µM] was to (E,E)-α-farnesene, one of the most abundant compounds in the male pheromone blend. This odorant was used in cocrystallization experiments, yielding the structure of CcapOBP22. The monomeric structure shows the typical OBP folding, constituted by six α-helical elements interconnected by three disulphide bridges. A C-terminal seventh α-helix constitutes the wall of a deep, L-shaped hydrophobic cavity. Analysis of the electron density in this cavity suggested trapping of farnesene in the crystal structure, although with partial occupancy. Superposition of the CcapOBP22 structure with related seven-helical OBPs highlights striking similarity in the organization of the C-terminal segment of these proteins. Collectively, our molecular and physiological data on medfly CcapOBP22 suggest its involvement in intersex olfactory communication.

    Organizational Affiliation: 

    Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.



Macromolecules
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Odorant binding protein OBP69a A124Ceratitis capitataMutation(s): 0 
Gene Names: OBP69a
Find proteins for W8W3V2 (Ceratitis capitata)
Explore W8W3V2 
Go to UniProtKB:  W8W3V2
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PG0
Query on PG0
Download Ideal Coordinates CCD File 
A
2-(2-METHOXYETHOXY)ETHANOL
C5 H12 O3
SBASXUCJHJRPEV-UHFFFAOYSA-N		 Ligand Interaction
SO4
Query on SO4
Download Ideal Coordinates CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L		 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.52 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.194 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 43.03α = 90
b = 43.03β = 90
c = 136.372γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
MOSFLMdata reduction
Aimlessdata scaling
BALBESphasing

Structure Validation

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View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2018-12-26
    Type: Initial release
  • Version 1.1: 2019-01-30
    Changes: Data collection, Database references
  • Version 1.2: 2019-06-05
    Changes: Data collection, Database references