2OUL

The Structure of Chagasin in Complex with a Cysteine Protease Clarifies the Binding Mode and Evolution of a New Inhibitor Family


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.20 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.186 
  • R-Value Observed: 0.189 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

The structure of chagasin in complex with a cysteine protease clarifies the binding mode and evolution of an inhibitor family.

Wang, S.X.Pandey, K.C.Scharfstein, J.Whisstock, J.Huang, R.K.Jacobelli, J.Fletterick, R.J.Rosenthal, P.J.Abrahamson, M.Brinen, L.S.Rossi, A.Sali, A.McKerrow, J.H.

(2007) Structure 15: 535-543

  • DOI: 10.1016/j.str.2007.03.012
  • Primary Citation of Related Structures:  
    2OUL

  • PubMed Abstract: 
  • Protein inhibitors of proteolytic enzymes regulate proteolysis and prevent the pathological effects of excess endogenous or exogenous proteases. Cysteine proteases are a large family of enzymes found throughout the plant and animal kingdoms. Disturbance of the equilibrium between cysteine proteases and natural inhibitors is a key event in the pathogenesis of cancer, rheumatoid arthritis, osteoporosis, and emphysema ...

    Protein inhibitors of proteolytic enzymes regulate proteolysis and prevent the pathological effects of excess endogenous or exogenous proteases. Cysteine proteases are a large family of enzymes found throughout the plant and animal kingdoms. Disturbance of the equilibrium between cysteine proteases and natural inhibitors is a key event in the pathogenesis of cancer, rheumatoid arthritis, osteoporosis, and emphysema. A family (I42) of cysteine protease inhibitors (http://merops.sanger.ac.uk) was discovered in protozoan parasites and recently found widely distributed in prokaryotes and eukaryotes. We report the 2.2 A crystal structure of the signature member of the I42 family, chagasin, in complex with a cysteine protease. Chagasin has a unique variant of the immunoglobulin fold with homology to human CD8alpha. Interactions of chagasin with a target protease are reminiscent of the cystatin family inhibitors. Protein inhibitors of cysteine proteases may have evolved more than once on nonhomologous scaffolds.


    Organizational Affiliation

    Department of Pathology, University of California, San Francisco, San Francisco, CA 94143, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Falcipain 2A241Plasmodium falciparum 3D7Mutation(s): 0 
Gene Names: AAF97809PF3D7_1115700
EC: 3.4.22
UniProt
Find proteins for Q8I6U4 (Plasmodium falciparum (isolate 3D7))
Explore Q8I6U4 
Go to UniProtKB:  Q8I6U4
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8I6U4
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
ChagasinB110Trypanosoma cruziMutation(s): 0 
Gene Names: cha
UniProt
Find proteins for Q966X9 (Trypanosoma cruzi)
Explore Q966X9 
Go to UniProtKB:  Q966X9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ966X9
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.20 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.186 
  • R-Value Observed: 0.189 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 94.236α = 90
b = 94.236β = 90
c = 119.764γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing
ADSCdata collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-02-26
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Source and taxonomy, Version format compliance
  • Version 1.2: 2018-01-24
    Changes: Structure summary
  • Version 1.3: 2019-07-24
    Changes: Data collection, Refinement description