Solution structure of the Trypanosoma cruzi cysteine protease inhibitor chagasin

Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the lowest energy 

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This is version 1.5 of the entry. See complete history


Solution Structure and Backbone Dynamics of the Trypanosoma cruzi Cysteine Protease Inhibitor Chagasin

Salmon, D.do Aido-Machado, R.Diehl, A.Leidert, M.Schmetzer, O.de Lima, A.A.P.Scharfstein, J.Oschkinat, H.Pires, J.R.

(2006) J Mol Biol 357: 1511-1521

  • DOI: https://doi.org/10.1016/j.jmb.2006.01.064
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    A Trypanosoma cruzi cysteine protease inhibitor, termed chagasin, is the first characterized member of a new family of tight-binding cysteine protease inhibitors identified in several lower eukaryotes and prokaryotes but not present in mammals. In the protozoan parasite T.cruzi, chagasin plays a role in parasite differentiation and in mammalian host cell invasion, due to its ability to modulate the endogenous activity of cruzipain, a lysosomal-like cysteine protease. In the present work, we determined the solution structure of chagasin and studied its backbone dynamics by NMR techniques. Structured as a single immunoglobulin-like domain in solution, chagasin exerts its inhibitory activity on cruzipain through conserved residues placed in three loops in the same side of the structure. One of these three loops, L4, predicted to be of variable length among chagasin homologues, is flexible in solution as determined by measurements of (15)N relaxation. The biological implications of structural homology between chagasin and other members of the immunoglobulin super-family are discussed.

  • Organizational Affiliation

    Instituto de Bioquímica Médica, CCS, Universidade Federal do Rio de Janeiro, Av. Brigadeiro Trompowiski s/n, Rio de Janeiro, RJ 21941-590, Brazil.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Chagasin111Trypanosoma cruziMutation(s): 0 
Gene Names: cha
Find proteins for Q966X9 (Trypanosoma cruzi)
Explore Q966X9 
Go to UniProtKB:  Q966X9
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UniProt GroupQ966X9
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-04-04
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2020-02-05
    Changes: Data collection, Database references, Derived calculations, Other
  • Version 1.4: 2023-06-14
    Changes: Database references, Other
  • Version 1.5: 2024-05-08
    Changes: Data collection, Database references