Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


Characterization of two distinct modes of drug binding to human intestinal Fatty Acid binding protein.

Patil, R.Laguerre, A.Wielens, J.Headey, S.J.Williams, M.L.Hughes, M.L.Mohanty, B.Porter, C.J.Scanlon, M.J.

(2014) ACS Chem Biol 9: 2526-2534

  • DOI: https://doi.org/10.1021/cb5005178
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    The aqueous cytoplasm of cells poses a potentially significant barrier for many lipophilic drugs to reach their sites of action. Fatty acid binding proteins (FABPs) bind to poorly water-soluble fatty acids (FAs) and lipophilic compounds and facilitate their intracellular transport. Several structures of FA in complex with FABPs have been described, but data describing the binding sites of other lipophilic ligands including drugs are limited. Here the environmentally sensitive fluorophores, 1-anilinonapthalene 8-sulfonic acid (ANS), and 11-dansylamino undecanoic acid (DAUDA) were used to investigate drug binding to human intestinal FABP (hIFABP). Most drugs that bound hIFABP were able to displace both ANS and DAUDA. A notable exception was ketorolac, a non-steroidal anti-inflammatory drug that bound to hIFABP and displaced DAUDA but failed to displace ANS. Isothermal titration calorimetry revealed that for the majority of ligands including FA, ANS, and DAUDA, binding to hIFABP was exothermic. In contrast, ketorolac binding to hIFABP was endothermic and entropy-driven. The X-ray crystal structure of DAUDA-hIFABP revealed a FA-like binding mode where the carboxylate of DAUDA formed a network of hydrogen bonds with residues at the bottom of the binding cavity and the dansyl group interacted with residues in the portal region. In contrast, NMR chemical shift perturbation (CSP) data suggested that ANS bound only toward the bottom of the hIFABP cavity, whereas ketorolac occupied only the portal region. The CSP data further suggested that ANS and ketorolac were able to bind simultaneously to hIFABP, consistent with the lack of displacement of ANS observed by fluorescence and supported by a model of the ternary complex. The NMR solution structure of the ketorolac-hIFABP complex therefore describes a newly characterized, hydrophobic ligand binding site in the portal region of hIFABP.

  • Organizational Affiliation

    Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences and ∥Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University , 381 Royal Parade, Parkville, Victoria 3052, Australia.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Fatty acid-binding protein, intestinal131Homo sapiensMutation(s): 0 
Gene Names: FABP2FABPI
UniProt & NIH Common Fund Data Resources
Find proteins for P12104 (Homo sapiens)
Explore P12104 
Go to UniProtKB:  P12104
PHAROS:  P12104
GTEx:  ENSG00000145384 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP12104
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on KTR

Download Ideal Coordinates CCD File 
B [auth A](1R)-5-benzoyl-2,3-dihydro-1H-pyrrolizine-1-carboxylic acid
C15 H13 N O3
Binding Affinity Annotations 
IDSourceBinding Affinity
KTR BindingDB:  2MJI Ki: 9400 (nM) from 1 assay(s)
Kd: 5.67e+4 (nM) from 1 assay(s)
-TΔS: -2.55e+1 (kJ/mol) from 1 assay(s)
ΔH: 0.3 (kJ/mol) from 1 assay(s)
ΔG: -2.52e+1 (kJ/mol) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-10-29
    Type: Initial release
  • Version 1.1: 2014-12-24
    Changes: Database references
  • Version 1.2: 2024-05-01
    Changes: Data collection, Database references, Derived calculations