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 

wwPDB Validation   3D Report Full Report


This is version 1.2 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: 10.1016/j.jmb.2008.06.040
  • Primary Citation of Related Structures:  
    2H54, 2H51, 2H4Y, 2H4W

  • 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 liga ...

    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)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Caspase-1 A178Homo sapiensMutation(s): 0 
Gene Names: CASP1, IL1BC, IL1BCE
EC: 3.4.22.36
Find proteins for P29466 (Homo sapiens)
Explore P29466 
Go to UniProtKB:  P29466
NIH Common Fund Data Resources
PHAROS:  P29466
GTEx:  ENSG00000137752
Protein Feature View
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  • Reference Sequence
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Caspase-1 B88Homo sapiensMutation(s): 1 
Gene Names: CASP1, IL1BC, IL1BCE
EC: 3.4.22.36
Find proteins for P29466 (Homo sapiens)
Explore P29466 
Go to UniProtKB:  P29466
NIH Common Fund Data Resources
PHAROS:  P29466
GTEx:  ENSG00000137752
Protein Feature View
Expand
  • Reference Sequence
  • Find similar proteins by:  Sequence   |   Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
N-[(benzyloxy)carbonyl]-L-valyl-N-[(2S)-1-carboxy-4-fluoro-3-oxobutan-2-yl]-L-alaninamide C5N/AMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Biologically Interesting Molecules (External Reference) 1 Unique
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 

  • 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