Biological Assembly 1  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 57.48 kDa 
• Atom Count: 3766 
• Modelled Residue Count: 461 
• Deposited Residue Count: 506 
• Unique protein chains: 1

1K88

Crystal structure of procaspase-7

• DOI: 10.2210/pdb1K88/pdb

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


• Deposited: 2001-10-23 Released: 2001-11-21 
• Deposition Author(s): Chai, J., Wu, Q., Shiozaki, E., Srinivasa, S.M., Alnemri, E.S., Shi, Y.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.253 
• R-Value Work: 0.227 
• R-Value Observed: 0.231 

Literature

Crystal structure of a procaspase-7 zymogen: mechanisms of activation and substrate binding

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

(2001) Cell 107: 399-407

• PubMed: 11701129 
• DOI: 10.1016/s0092-8674(01)00544-x
• Primary Citation of Related Structures:  
  1K88, 1K86


• PubMed Abstract: 
  

Apoptosis is primarily executed by active caspases, which are derived from the inactive procaspase zymogens through proteolytic cleavage. Here we report the crystal structures of a caspase zymogen, procaspase-7, and an active caspase-7 without any bound inhibitors. Compared to the inhibitor-bound caspase-7, procaspase-7 zymogen exhibits significant structural differences surrounding the catalytic cleft, which precludes the formation of a productive conformation. Proteolytic cleavage between the large and small subunits allows rearrangement of essential loops in the active site, priming active caspase-7 for inhibitor/substrate binding. Strikingly, binding by inhibitors causes a 180 degrees flipping of the N terminus in the small subunit, which interacts with and stabilizes the catalytic cleft. These analyses reveal the structural mechanisms of caspase activation and demonstrate that the inhibitor/substrate binding is a process of induced fit.

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Organizational Affiliation: 

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

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
procaspase-7	A, B	253	Homo sapiens	Mutation(s): 2  Gene Names: CASP7, MCH3 EC: 3.4.22 (PDB Primary Data), 3.4.22.60 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P55210 (Homo sapiens) Explore P55210  Go to UniProtKB:  P55210
PHAROS:  P55210 GTEx:  ENSG00000165806

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.253 
• R-Value Work: 0.227 
• R-Value Observed: 0.231 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 91.2	α = 90
b = 91.2	β = 90
c = 185.2	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: 2001-10-23 
• Released Date: 2001-11-21 
Deposition Author(s): Chai, J., Wu, Q., Shiozaki, E., Srinivasa, S.M., Alnemri, E.S., Shi, Y.

Revision History  

• Version 1.0: 2001-11-21
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance