Crystal structure of XIAP BIR3 domain in complex with a Smac-mimetic compound

Experimental Data Snapshot

  • Resolution: 3.00 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.191 

wwPDB Validation   3D Report Full Report

Ligand Structure Quality Assessment 

This is version 1.2 of the entry. See complete history


Designing Smac-mimetics as antagonists of XIAP, cIAP1, and cIAP2.

Cossu, F.Mastrangelo, E.Milani, M.Sorrentino, G.Lecis, D.Delia, D.Manzoni, L.Seneci, P.Scolastico, C.Bolognesi, M.

(2009) Biochem Biophys Res Commun 378: 162-167

  • DOI: https://doi.org/10.1016/j.bbrc.2008.10.139
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Inhibitor of apoptosis proteins (IAPs) such as XIAP, cIAP1, and cIAP2 are upregulated in many cancer cells. Several compounds targeting IAPs and inducing cell death in cancer cells have been developed. Some of these are synthesized mimicking the N-terminal tetrapeptide sequence of Smac/DIABLO, the natural endogenous IAPs inhibitor. Starting from such conceptual design, we generated a library of 4-substituted azabicyclo[5.3.0]alkane Smac-mimetics. Here we report the crystal structure of the BIR3 domain from XIAP in complex with Smac037, a compound designed according to structural principles emerging from our previously analyzed XIAP BIR3/Smac-mimetic complexes. In parallel, we present an in silico docking analysis of three Smac-mimetics to the BIR3 domain of cIAP1, providing general considerations for the development of high affinity lead compounds targeting three members of the IAP family.

  • Organizational Affiliation

    Department of Biomolecular Sciences and Biotechnology, University of Milano, Via Celoria 26, I-20133 Milano, Italy.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Baculoviral IAP repeat-containing protein 4
A, B
122Homo sapiensMutation(s): 0 
EC: 6.3.2
UniProt & NIH Common Fund Data Resources
Find proteins for P98170 (Homo sapiens)
Explore P98170 
Go to UniProtKB:  P98170
PHAROS:  P98170
GTEx:  ENSG00000101966 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP98170
Sequence Annotations
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
SMK BindingDB:  3EYL Ki: 220 (nM) from 1 assay(s)
IC50: min: 86, max: 250 (nM) from 2 assay(s)
PDBBind:  3EYL IC50: 250 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 3.00 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.191 
  • Space Group: I 41 3 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 170.423α = 90
b = 170.423β = 90
c = 170.423γ = 90
Software Package:
Software NamePurpose
DNAdata collection
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report

Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-11-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2023-09-06
    Changes: Data collection, Database references, Derived calculations, Refinement description