Crystal structure of the globular domain of human calreticulin mutant D71K

Experimental Data Snapshot

  • Resolution: 2.30 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.210 
  • R-Value Observed: 0.212 

wwPDB Validation   3D Report Full Report

This is version 1.4 of the entry. See complete history


Structures of parasite calreticulins provide insights into their flexibility and dual carbohydrate/peptide-binding properties.

Moreau, C.Cioci, G.Iannello, M.Laffly, E.Chouquet, A.Ferreira, A.Thielens, N.M.Gaboriaud, C.

(2016) IUCrJ 3: 408-419

  • DOI: https://doi.org/10.1107/S2052252516012847
  • Primary Citation of Related Structures:  
    5HCA, 5HCB, 5HCF, 5LK5

  • PubMed Abstract: 

    Calreticulin (CRT) is a multifaceted protein, initially discovered as an endoplasmic reticulum (ER) chaperone protein, that is essential in calcium metabolism. Various implications in cancer, early development and immunology have been discovered more recently for CRT, as well as its role as a dominant 'eat-me' prophagocytic signal. Intriguingly, cell-surface exposure/secretion of CRT is among the infective strategies used by parasites such as Trypanosoma cruzi , Entamoeba histolytica , Taenia solium , Leishmania donovani and Schistosoma mansoni . Because of the inherent flexibility of CRTs, their analysis by X-ray crystallography requires the design of recombinant constructs suitable for crystallization, and thus only the structures of two very similar mammalian CRT lectin domains are known. With the X-ray structures of two distant parasite CRTs, insights into species structural determinants that might be harnessed to fight against the parasites without affecting the functions of the host CRT are now provided. Moreover, although the hypothesis that CRT can exhibit both open and closed conformations has been proposed in relation to its chaperone function, only the open conformation has so far been observed in crystal structures. The first evidence is now provided of a complex conformational transition with the junction reoriented towards P-domain closure. SAXS experiments also provided additional information about the flexibility of T. cruzi CRT in solution, thus complementing crystallographic data on the open conformation. Finally, regarding the conserved lectin-domain structure and chaperone function, evidence is provided of its dual carbohydrate/protein specificity and a new scheme is proposed to interpret such unusual substrate-binding properties. These fascinating features are fully consistent with previous experimental observations, as discussed considering the broad spectrum of CRT sequence conservations and differences.

  • Organizational Affiliation

    Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS , 38044 Grenoble, France.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J
265Homo sapiensMutation(s): 1 
Gene Names: CALRCRTC
UniProt & NIH Common Fund Data Resources
Find proteins for P27797 (Homo sapiens)
Explore P27797 
Go to UniProtKB:  P27797
PHAROS:  P27797
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP27797
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on CA

Download Ideal Coordinates CCD File 
K [auth A]
L [auth B]
M [auth C]
N [auth D]
O [auth E]
K [auth A],
L [auth B],
M [auth C],
N [auth D],
O [auth E],
Q [auth F],
R [auth G],
S [auth H],
T [auth I],
U [auth J]
Query on CL

Download Ideal Coordinates CCD File 
Experimental Data & Validation

Experimental Data

  • Resolution: 2.30 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.210 
  • R-Value Observed: 0.212 
  • Space Group: P 42
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 196.976α = 90
b = 196.976β = 90
c = 67.806γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XSCALEdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2016-08-31
    Type: Initial release
  • Version 1.1: 2016-11-09
    Changes: Database references
  • Version 1.2: 2016-12-21
    Changes: Database references
  • Version 1.3: 2018-08-01
    Changes: Data collection, Database references
  • Version 1.4: 2019-10-16
    Changes: Data collection