Macromolecule Content

• Total Structure Weight: 14.43 kDa 
• Atom Count: 1012 
• Residue Count: 126 
• Unique protein chains: 2

1G3F

NMR STRUCTURE OF A 9 RESIDUE PEPTIDE FROM SMAC/DIABLO COMPLEXED TO THE BIR3 DOMAIN OF XIAP

• DOI: 10.2210/pdb1G3F/pdb

• Classification: APOPTOSIS
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2000-10-24 Released: 2001-01-10 
• Deposition Author(s): Liu, Z., Sun, C., Olejniczak, E.T., Meadows, R.P., Betz, S.F., Oost, T., Herrmann, J., Wu, J.C., Fesik, S.W.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Literature

Structural basis for binding of Smac/DIABLO to the XIAP BIR3 domain.

Liu, Z., Sun, C., Olejniczak, E.T., Meadows, R.P., Betz, S.F., Oost, T., Herrmann, J., Wu, J.C., Fesik, S.W.

(2000) Nature 408: 1004-1008

• PubMed: 11140637 
• DOI: 10.1038/35050006
• Primary Citation of Related Structures:  
  1G3F


• PubMed Abstract: 
  

The inhibitor-of-apoptosis proteins (IAPs) regulate programmed cell death by inhibiting members of the caspase family of enzymes. Recently, a mammalian protein called Smac (also named DIABLO) was identified that binds to the IAPs and promotes caspase activation. Although undefined in the X-ray structure, the amino-terminal residues of Smac are critical for its function. To understand the structural basis for molecular recognition between Smac and the IAPs, we determined the solution structure of the BIR3 domain of X-linked IAP (XIAP) complexed with a functionally active nine-residue peptide derived from the N terminus of Smac. The peptide binds across the third beta-strand of the BIR3 domain in an extended conformation with only the first four residues contacting the protein. The complex is stabilized by four intermolecular hydrogen bonds, an electrostatic interaction involving the N terminus of the peptide, and several hydrophobic interactions. This structural information, along with the binding data from BIR3 and Smac peptide mutants reported here, should aid in the design of small molecules that may be used for the treatment of cancers that overexpress IAPs.

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Organizational Affiliation: 

Pharmaceutical Discovery Division, Abbott Laboratories, Abbott Park, Illinois 60064, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INHIBITOR OF APOPTOSIS PROTEIN 3	A	117	Homo sapiens	Mutation(s): 0  Gene Names: XIAP, API3, BIRC4, IAP3 EC: 2.3.2.27
Find proteins for P98170 (Homo sapiens) Explore P98170  Go to UniProtKB:  P98170
NIH Common Fund Data Resources
PHAROS  P98170 GTEx  ENSG00000101966

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
SMAC	B	9	N/A	Mutation(s): 0
Find proteins for Q9NR28 (Homo sapiens) Explore Q9NR28  Go to UniProtKB:  Q9NR28
NIH Common Fund Data Resources
PHAROS  Q9NR28 GTEx  ENSG00000184047

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	A	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Submitted: 1 
• OLDERADO: 1G3F Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2000-10-24 
• Released Date: 2001-01-10 
Deposition Author(s): Liu, Z., Sun, C., Olejniczak, E.T., Meadows, R.P., Betz, S.F., Oost, T., Herrmann, J., Wu, J.C., Fesik, S.W.

Revision History 

• Version 1.0: 2001-01-10
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance