3SAO

The Siderocalin Ex-FABP functions through dual ligand specificities


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Galline Ex-FABP Is an Antibacterial Siderocalin and a Lysophosphatidic Acid Sensor Functioning through Dual Ligand Specificities.

Correnti, C.Clifton, M.C.Abergel, R.J.Allred, B.Hoette, T.M.Ruiz, M.Cancedda, R.Raymond, K.N.Descalzi, F.Strong, R.K.

(2011) Structure 19: 1796-1806

  • DOI: 10.1016/j.str.2011.09.019

  • PubMed Abstract: 
  • Galline Ex-FABP was identified as another candidate antibacterial, catecholate siderophore binding lipocalin (siderocalin) based on structural parallels with the family archetype, mammalian Siderocalin. Binding assays show that Ex-FABP retains iron i ...

    Galline Ex-FABP was identified as another candidate antibacterial, catecholate siderophore binding lipocalin (siderocalin) based on structural parallels with the family archetype, mammalian Siderocalin. Binding assays show that Ex-FABP retains iron in a siderophore-dependent manner in both hypertrophic and dedifferentiated chondrocytes, where Ex-FABP expression is induced after treatment with proinflammatory agents, and specifically binds ferric complexes of enterobactin, parabactin, bacillibactin and, unexpectedly, monoglucosylated enterobactin, which does not bind to Siderocalin. Growth arrest assays functionally confirm the bacteriostatic effect of Ex-FABP in vitro under iron-limiting conditions. The 1.8 Å crystal structure of Ex-FABP explains the expanded specificity, but also surprisingly reveals an extended, multi-chambered cavity extending through the protein and encompassing two separate ligand specificities, one for bacterial siderophores (as in Siderocalin) at one end and one specifically binding copurified lysophosphatidic acid, a potent cell signaling molecule, at the other end, suggesting Ex-FABP employs dual functionalities to explain its diverse endogenous activities.


    Organizational Affiliation

    Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Extracellular fatty acid-binding protein
A, B
160Gallus gallusMutation(s): 3 
Gene Names: EXFABP
Find proteins for P21760 (Gallus gallus)
Go to UniProtKB:  P21760
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
DBH
Query on DBH

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Download CCD File 
B
2,3-DIHYDROXY-BENZOIC ACID
C7 H6 O4
GLDQAMYCGOIJDV-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

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Download CCD File 
B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
NKN
Query on NKN

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Download CCD File 
A, B
(2R)-2-hydroxy-3-(phosphonooxy)propyl tetradecanoate
14:0 LPA, myristoyl lysophosphatidic acid
C17 H35 O7 P
FAZBDRGXCKPVJU-MRXNPFEDSA-N
 Ligand Interaction
FE
Query on FE

Download SDF File 
Download CCD File 
B
FE (III) ION
Fe
VTLYFUHAOXGGBS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.202 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 37.950α = 90.00
b = 68.890β = 90.00
c = 117.400γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
d*TREKdata reduction
d*TREKdata scaling
REFMACrefinement
ADSCdata collection
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-12-28
    Type: Initial release