Biological Assembly 1  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 4-mer - A2B2 

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

Macromolecule Content

• Total Structure Weight: 84.92 kDa 
• Atom Count: 3974 
• Residue Count: 498 
• Unique protein chains: 3

1I51

CRYSTAL STRUCTURE OF CASPASE-7 COMPLEXED WITH XIAP

• DOI: 10.2210/pdb1I51/pdb

• Classification: HYDROLASE/HYDROLASE INHIBITOR
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2001-02-23 Released: 2002-02-23 
• Deposition Author(s): Chai, J., Shi, Y.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.45 Å
• R-Value Free: 0.272 
• R-Value Work: 0.233 
• R-Value Observed: 0.235 

Literature

Structural basis of caspase-7 inhibition by XIAP.

Chai, J., Shiozaki, E., Srinivasula, S.M., Wu, Q., Datta, P., Alnemri, E.S., Shi, Y., Dataa, P.

(2001) Cell 104: 769-780

• PubMed: 11257230 
• DOI: 10.1016/s0092-8674(01)00272-0
• Primary Citation of Related Structures:  
  1I51


• PubMed Abstract: 
  

The inhibitor of apoptosis (IAP) proteins suppress cell death by inhibiting the catalytic activity of caspases. Here we present the crystal structure of caspase-7 in complex with a potent inhibitory fragment from XIAP at 2.45 A resolution. An 18-residue XIAP peptide binds the catalytic groove of caspase-7, making extensive contacts to the residues that are essential for its catalytic activity. Strikingly, despite a reversal of relative orientation, a subset of interactions between caspase-7 and XIAP closely resemble those between caspase-7 and its tetrapeptide inhibitor DEVD-CHO. Our biochemical and structural analyses reveal that the BIR domains are dispensable for the inhibition of caspase-3 and -7. This study provides a structural basis for the design of the next-generation caspase inhibitors.

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Organizational Affiliation: 

Department of Molecular Biology, Princeton University, Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CASPASE-7 SUBUNIT P20	A, C	148	Homo sapiens	Mutation(s): 1  Gene Names: CASP7, MCH3 EC: 3.4.22 (PDB Primary Data), 3.4.22.60 (UniProt)
Find proteins for P55210 (Homo sapiens) Explore P55210  Go to UniProtKB:  P55210
NIH Common Fund Data Resources
PHAROS:  P55210 GTEx:  ENSG00000165806

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
CASPASE-7 SUBUNIT P11	B, D	105	Homo sapiens	Mutation(s): 0  Gene Names: CASP7, MCH3 EC: 3.4.22 (PDB Primary Data), 3.4.22.60 (UniProt)
Find proteins for P55210 (Homo sapiens) Explore P55210  Go to UniProtKB:  P55210
NIH Common Fund Data Resources
PHAROS:  P55210 GTEx:  ENSG00000165806

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
X-LINKED INHIBITOR OF APOPTOSIS PROTEIN	E, F	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

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.45 Å
• R-Value Free: 0.272 
• R-Value Work: 0.233 
• R-Value Observed: 0.235 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 89.6	α = 90
b = 89.6	β = 90
c = 185.5	γ = 120

Software Package:

Software Name	Purpose
AMoRE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-02-23 
• Released Date: 2002-02-23 
Deposition Author(s): Chai, J., Shi, Y.

Revision History 

• Version 1.0: 2002-02-23
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance