4WVU

CRYSTAL STRUCTURE OF XIAP-BIR2 DOMAIN COMPLEXED WITH LIGAND BOUND

• PDB DOI: https://doi.org/10.2210/pdb4WVU/pdb

• Classification: APOPTOSIS
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2014-11-07 Released: 2015-03-04 
• Deposition Author(s): Pokross, M.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.02 Å
• R-Value Free: 0.178 
• R-Value Work: 0.139 
• R-Value Observed: 0.141 

Literature

The Discovery of Macrocyclic XIAP Antagonists from a DNA-Programmed Chemistry Library, and Their Optimization To Give Lead Compounds with in Vivo Antitumor Activity.

Seigal, B.A., Connors, W.H., Fraley, A., Borzilleri, R.M., Carter, P.H., Emanuel, S.L., Fargnoli, J., Kim, K., Lei, M., Naglich, J.G., Pokross, M.E., Posy, S.L., Shen, H., Surti, N., Talbott, R., Zhang, Y., Terrett, N.K.

(2015) J Med Chem 58: 2855-2861

• PubMed: 25695766 
• DOI: https://doi.org/10.1021/jm501892g
• Primary Citation of Related Structures:  
  4WVS, 4WVT, 4WVU


• PubMed Abstract: 
  

  Affinity selection screening of macrocycle libraries derived from DNA-programmed chemistry identified XIAP BIR2 and BIR3 domain inhibitors that displace bound pro-apoptotic caspases. X-ray cocrystal structures of key compounds with XIAP BIR2 suggested potency-enhancing structural modifications. Optimization of dimeric macrocycles with similar affinity for both domains were potent pro-apoptotic agents in cancer cell lines and efficacious in shrinking tumors in a mouse xenograft model.

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Organizational Affiliation: 

†Ensemble Therapeutics Corp, 99 Erie Street, Cambridge, Massachusetts 02139, United States.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 12.36 kDa 
• Atom Count: 778 
• Modelled Residue Count: 84 
• Deposited Residue Count: 103 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
E3 ubiquitin-protein ligase XIAP	A	98	Homo sapiens	Mutation(s): 2  Gene Names: XIAP, API3, BIRC4, IAP3 EC: 6.3.2 (PDB Primary Data), 2.3.2.27 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P98170 (Homo sapiens) Explore P98170  Go to UniProtKB:  P98170
PHAROS:  P98170 GTEx:  ENSG00000101966

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
3,11-DIFLUORO-6,8,13-TRIMETHYL-8H-QUINO[4,3,2-KL]ACRIDIN-13-IUM	B	5	N/A	Mutation(s): 0

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	D [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L
GOL	E [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
ZN	C [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Modified Residues  2 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
HOX	B	L-PEPTIDE LINKING	C9 H12 N2 O2		PHE
MAA	B	L-PEPTIDE LINKING	C4 H9 N O2		ALA

Biologically Interesting Molecules (External Reference) 1 Unique

Entity ID: 2
ID	Chains	Name	Type/Class	2D Diagram	3D Interactions
PRD_002132	B	(3,11-DIFLUORO-6,8,13-TRIMETHYL-8H-QUINO[4,3,2-KL]ACRIDIN-13-IUM	Cyclic peptide / Antagonist

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.02 Å
• R-Value Free: 0.178 
• R-Value Work: 0.139 
• R-Value Observed: 0.141 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 28.261	α = 90
b = 39.328	β = 95.51
c = 33.058	γ = 90

Software Package:

Software Name	Purpose
XDS	data reduction
SCALA	data scaling
BUSTER	refinement
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2015-03-04 
Deposition Author(s): Pokross, M.E.

Revision History  

• Version 1.0: 2015-03-04
  Type: Initial release
  
• Version 1.1: 2015-04-08
  Changes: Database references
• Version 2.0: 2023-11-15
  Changes: Atomic model, Data collection, Database references, Derived calculations, Other, Source and taxonomy