2H54

Crystal structure of human caspase-1 (Thr388->Ala) in complex with 3-[2-(2-benzyloxycarbonylamino-3-methyl-butyrylamino)-propionylamino]-4-oxo-pentanoic acid (z-VAD-FMK)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.217 

Starting Model: experimental
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wwPDB Validation   3D Report Full Report


This is version 1.5 of the entry. See complete history


Literature

An allosteric circuit in caspase-1.

Datta, D.Scheer, J.M.Romanowski, M.J.Wells, J.A.

(2008) J Mol Biol 381: 1157-1167

  • DOI: https://doi.org/10.1016/j.jmb.2008.06.040
  • Primary Citation of Related Structures:  
    2H4W, 2H4Y, 2H51, 2H54

  • PubMed Abstract: 

    Structural studies of caspase-1 reveal that the dimeric thiol protease can exist in two states: in an on-state, when the active site is occupied, or in an off-state, when the active site is empty or when the enzyme is bound by a synthetic allosteric ligand at the dimer interface approximately 15 A from the active site. A network of 21 hydrogen bonds from nine side chains connecting the active and allosteric sites change partners when going between the on-state and the off-state. Alanine-scanning mutagenesis of these nine side chains shows that only two of them-Arg286 and Glu390, which form a salt bridge-have major effects, causing 100- to 200-fold reductions in catalytic efficiency (k(cat)/K(m)). Two neighbors, Ser332 and Ser339, have minor effects, causing 4- to 7-fold reductions. A more detailed mutational analysis reveals that the enzyme is especially sensitive to substitutions of the salt bridge: even a homologous R286K substitution causes a 150-fold reduction in k(cat)/K(m). X-ray crystal structures of these variants suggest the importance of both the salt bridge interaction and the coordination of solvent water molecules near the allosteric binding pocket. Thus, only a small subset of side chains from the larger hydrogen bonding network is critical for activity. These form a contiguous set of interactions that run from one active site through the allosteric site at the dimer interface and onto the second active site. This subset constitutes a functional allosteric circuit or "hot wire" that promotes site-to-site coupling.


  • Organizational Affiliation

    Departments of Pharmaceutical Chemistry and Cellular and Molecular Pharmacology, University of California at San Francisco, San Francisco, CA 94143, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Caspase-1178Homo sapiensMutation(s): 0 
Gene Names: CASP1IL1BCIL1BCE
EC: 3.4.22.36
UniProt & NIH Common Fund Data Resources
Find proteins for P29466 (Homo sapiens)
Explore P29466 
Go to UniProtKB:  P29466
PHAROS:  P29466
GTEx:  ENSG00000137752 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP29466
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Caspase-188Homo sapiensMutation(s): 1 
Gene Names: CASP1IL1BCIL1BCE
EC: 3.4.22.36
UniProt & NIH Common Fund Data Resources
Find proteins for P29466 (Homo sapiens)
Explore P29466 
Go to UniProtKB:  P29466
PHAROS:  P29466
GTEx:  ENSG00000137752 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP29466
Sequence Annotations
Expand
  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
N-[(benzyloxy)carbonyl]-L-valyl-N-[(2S)-1-carboxy-4-fluoro-3-oxobutan-2-yl]-L-alaninamide5N/AMutation(s): 0 
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.217 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 63.249α = 90
b = 63.249β = 90
c = 162.101γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
CrystalCleardata reduction
d*TREKdata scaling
AMoREphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-03-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary, Version format compliance
  • Version 1.2: 2012-12-12
    Changes: Other
  • Version 1.3: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-08-30
    Changes: Data collection, Refinement description
  • Version 1.5: 2024-10-16
    Changes: Structure summary