1QTN

CRYSTAL STRUCTURE OF THE COMPLEX OF CASPASE-8 WITH THE TETRAPEPTIDE INHIBITOR ACE-IETD-ALDEHYDE

• PDB DOI: https://doi.org/10.2210/pdb1QTN/pdb

• Classification: HYDROLASE/HYDROLASE INHIBITOR
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-06-28 Released: 2000-09-20 
• Deposition Author(s): Watt, W., Watenpaugh, K.D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.188 
• R-Value Work: 0.143 
• R-Value Observed: 0.166 

Literature

The atomic-resolution structure of human caspase-8, a key activator of apoptosis.

Watt, W., Koeplinger, K.A., Mildner, A.M., Heinrikson, R.L., Tomasselli, A.G., Watenpaugh, K.D.

(1999) Structure 7: 1135-1143

• PubMed: 10508785 
• DOI: https://doi.org/10.1016/s0969-2126(99)80180-4
• Primary Citation of Related Structures:  
  1QTN


• PubMed Abstract: 
  

  Caspases are a family of cysteine proteases that have important intracellular roles in inflammation and apoptosis. Caspase-8 activates downstream caspases which are unable to carry out autocatalytic processing and activation. Caspase-8 is designated as an initiator caspase and is believed to sit at the apex of the Fas- or TNF-mediated apoptotic cascade. In view of this role, the enzyme is an attractive target for the design of inhibitors aimed at blocking the undesirable cell death associated with a range of degenerative disorders.

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Organizational Affiliation: 

Structural, Analytical & Medicinal Chemistry Pharmacia & Upjohn Inc. 301 Henrietta Street, Kalamazoo, MI 49007, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Hetero 6-mer - A2B2C2 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 6-mer - A2B2C1D1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 30.33 kDa 
• Atom Count: 2,324 
• Modelled Residue Count: 247 
• Deposited Residue Count: 264 
• Unique protein chains: 3

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CASPASE-8	A	164	Homo sapiens	Mutation(s): 0  EC: 3.4.22
UniProt & NIH Common Fund Data Resources
Find proteins for Q14790 (Homo sapiens) Explore Q14790  Go to UniProtKB:  Q14790
PHAROS:  Q14790 GTEx:  ENSG00000064012

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
CASPASE-8	B	95	Homo sapiens	Mutation(s): 0  EC: 3.4.22
UniProt & NIH Common Fund Data Resources
Find proteins for Q14790 (Homo sapiens) Explore Q14790  Go to UniProtKB:  Q14790
PHAROS:  Q14790 GTEx:  ENSG00000064012

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
ACETYL-ILE-GLU-THR-ASP-ALDEHYDE	C	5	N/A	Mutation(s): 0

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
DTD	D [auth A], E [auth B]	DITHIANE DIOL C4 H8 O2 S2 YPGMOWHXEQDBBV-IMJSIDKUSA-N

Biologically Interesting Molecules (External Reference) 1 Unique

Entity ID: 3
ID	Chains	Name	Type/Class	2D Diagram	3D Interactions
PRD_000301	C	N-(2-oxoethyl)-L-isoleucyl-L-alpha-glutamyl-N-[(1R)-2-carboxy-1-formylethyl]-L-threoninamide	Peptide-like / Inhibitor

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.188 
• R-Value Work: 0.143 
• R-Value Observed: 0.166 
• Space Group: P 3₁ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 62.4	α = 90
b = 62.4	β = 90
c = 129.25	γ = 120

Software Package:

Software Name	Purpose
AMoRE	phasing
SHELXL-97	refinement
SMART	data reduction
SAINT	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-09-20 
Deposition Author(s): Watt, W., Watenpaugh, K.D.

Revision History  

• Version 1.0: 2000-09-20
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary, Version format compliance
• Version 1.3: 2012-04-04
  Changes: Structure summary
• Version 1.4: 2012-12-12
  Changes: Other
• Version 1.5: 2023-08-16
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.6: 2023-11-15
  Changes: Data collection