2IFB

CRYSTAL STRUCTURE OF RAT INTESTINAL FATTY-ACID-BINDING PROTEIN. REFINEMENT AND ANALYSIS OF THE ESCHERICHIA COLI-DRIVED PROTEIN WITH BOUND PALMITATE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.178 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Crystal structure of rat intestinal fatty-acid-binding protein. Refinement and analysis of the Escherichia coli-derived protein with bound palmitate.

Sacchettini, J.C.Gordon, J.I.Banaszak, L.J.

(1989) J Mol Biol 208: 327-339

  • DOI: https://doi.org/10.1016/0022-2836(89)90392-6
  • Primary Citation of Related Structures:  
    2IFB

  • PubMed Abstract: 

    Rat intestinal fatty-acid-binding protein (I-FABP) is a small (15,124 Mr) cytoplasmic polypeptide that binds long-chain fatty acids in a non-covalent fashion. I-FABP is a member of a family of intracellular binding proteins that are thought to participate in the uptake, transport and/or metabolic targeting of hydrophobic ligands. The crystal structure of Escherichia coli-derived rat I-FABP with a single molecule of bound palmitate has been refined to 2 A resolution using a combination of least-squares methods, energy refinement and molecular dynamics. The combined methods resulted in a model with a crystallographic R-factor of 17.8% (7775 reflections, sigma greater than 2.0), root-mean-square bond length deviation of 0.009 A and root-mean-square bond angle deviation of 2.85 degrees. I-FABP contains ten antiparallel beta-strands organized into two approximately orthogonal, beta-sheets. The hydrocarbon tail of its single C16:0 ligand is present in a well-ordered, distinctively bent conformation. The carboxylate group of the fatty acid is located in the interior of I-FABP and forms a unique "quintet" of electrostatic interactions involving Arg106; Gln 115, and two solvent molecules. The hydrocarbon tail is bent with a slight left-handed helical twist from the carboxylate group to C-16. The bent methylene chain resides in a "cradle" formed by the side-chains of hydrophobic, mainly aromatic, amino acid residues. The refined molecular model of holo-I-FABP suggests several potential locations for entry and exiting of the fatty acid.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO 63110.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
INTESTINAL FATTY ACID BINDING PROTEIN131Rattus norvegicusMutation(s): 0 
UniProt
Find proteins for P02693 (Rattus norvegicus)
Explore P02693 
Go to UniProtKB:  P02693
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP02693
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
PLM
Query on PLM

Download Ideal Coordinates CCD File 
B [auth A]PALMITIC ACID
C16 H32 O2
IPCSVZSSVZVIGE-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.178 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 36.8α = 90
b = 56.9β = 114
c = 31.9γ = 90
Software Package:
Software NamePurpose
X-PLORrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1992-01-15
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references, Derived calculations, Other