Macromolecule Content

• Total Structure Weight: 13.77 kDa 
• Atom Count: 946 
• Modelled Residue Count: 117 
• Deposited Residue Count: 120 
• Unique protein chains: 1

1F9X

AVERAGE NMR SOLUTION STRUCTURE OF THE BIR-3 DOMAIN OF XIAP

• DOI: 10.2210/pdb1F9X/pdb

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


• Deposited: 2000-07-11 Released: 2001-07-11 
• Deposition Author(s): Sun, C., Cai, M., Meadows, R.P., Fesik, S.W.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Literature

NMR structure and mutagenesis of the third Bir domain of the inhibitor of apoptosis protein XIAP.

Sun, C., Cai, M., Meadows, R.P., Xu, N., Gunasekera, A.H., Herrmann, J., Wu, J.C., Fesik, S.W.

(2000) J Biol Chem 275: 33777-33781

• PubMed: 10934209 
• DOI: 10.1074/jbc.M006226200
• Primary Citation of Related Structures:  
  1F9X


• PubMed Abstract: 
  

The inhibitor of apoptosis proteins (IAPs) regulate the caspase family of cysteine proteases, which play an important role in the execution of programmed cell death. Human X-linked inhibitor of apoptosis protein (XIAP) is a potent inhibitor of caspases-3, -7, and -9. Here we show that the Bir3 domain is the minimal region of XIAP that is needed for potent caspase-9 inhibition. The three-dimensional structure of the Bir3 domain of XIAP, determined by NMR spectroscopy, resembles a classical zinc finger and consists of five alpha-helices, a three-stranded beta-sheet, and a zinc atom chelated to three cysteines and one histidine. The structure of the Bir3 domain is similar to that of the Bir2 domain of XIAP but differs from the previously determined structure of the Bir3 domain of MIHB. Based on site-directed mutagenesis, we have identified the regions of the Bir3 domain of XIAP that are important for inhibiting caspase-9. Despite the structural similarities of the Bir2 and Bir3 domain of XIAP, a different set of residues were found to be critical for inhibiting the individual caspases. These results suggest that XIAP inhibits caspase-3 and caspase-9 in a different manner.

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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 XIAP	A	120	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

Small Molecules

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

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Submitted: 1 
• OLDERADO: 1F9X Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2000-07-11 
• Released Date: 2001-07-11 
Deposition Author(s): Sun, C., Cai, M., Meadows, R.P., Fesik, S.W.

Revision History  

• Version 1.0: 2001-07-11
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance