Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Predict Membrane 

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 80.36 kDa 
• Atom Count: 5514 
• Modelled Residue Count: 680 
• Deposited Residue Count: 724 
• Unique protein chains: 1

1FEP

FERRIC ENTEROBACTIN RECEPTOR

• PDB DOI: 10.2210/pdb1FEP/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Escherichia coli K-12
• Mutation(s): Yes 
• Membrane Protein: Yes  OPMPDBTMMemProtMDmpstruc


• Deposited: 1998-11-24 Released: 1999-01-13 
• Deposition Author(s): Buchanan, S.K., Smith, B.S., Ventatramani, L., Xia, D., Esser, L., Palnitkar, M., Chakraborty, R., Van Der Helm, D., Deisenhofer, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.282 
• R-Value Work: 0.236 

Literature

Crystal structure of the outer membrane active transporter FepA from Escherichia coli.

Buchanan, S.K., Smith, B.S., Venkatramani, L., Xia, D., Esser, L., Palnitkar, M., Chakraborty, R., van der Helm, D., Deisenhofer, J.

(1999) Nat Struct Biol 6: 56-63

• PubMed: 9886293 
• DOI: 10.1038/4931
• Primary Citation of Related Structures:  
  1FEP


• PubMed Abstract: 
  

Integral outer membrane receptors for iron chelates and vitamin B12 carry out specific ligand transport against a concentration gradient. Energy for active transport is obtained from the proton-motive force of the inner membrane through physical interaction with TonB-ExbB-ExbD, an inner membrane complex. Here we report the crystal structure of an active transport, outer membrane receptor at 2.4 A resolution. Two distinct functional domains are revealed: (i) a 22-stranded beta-barrel that spans the outer membrane and contains large extracellular loops which appear to function in ligand binding; and (ii) a globular N-terminal domain that folds into the barrel pore, inhibiting access to the periplasm and contributing two additional loops for potential ligand binding. These loops could provide a signaling pathway between the processes of ligand recognition and TonB-mediated transport. The blockage of the pore suggests that the N-terminal domain must undergo a conformational rearrangement to allow ligand transport into the periplasm.

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Organizational Affiliation: 

Howard Hughes Medical Institute, and Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235-9050, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
FERRIC ENTEROBACTIN RECEPTOR	A	724	Escherichia coli K-12	Mutation(s): 11  Gene Names: fepA, fep, feuB, b0584, JW5086 Membrane Entity: Yes
UniProt
Find proteins for P05825 (Escherichia coli (strain K12)) Explore P05825  Go to UniProtKB:  P05825

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.282 
• R-Value Work: 0.236 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 112.3	α = 90
b = 127.6	β = 90
c = 135.7	γ = 90

Software Package:

Software Name	Purpose
MLPHARE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1998-11-24 
• Released Date: 1999-01-13 
Deposition Author(s): Buchanan, S.K., Smith, B.S., Ventatramani, L., Xia, D., Esser, L., Palnitkar, M., Chakraborty, R., Van Der Helm, D., Deisenhofer, J.

Revision History  

• Version 1.0: 1999-01-13
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance