5O46

Crystal structure of Iristatin, a secreted salivary cystatin from the hard tick Ixodes ricinus

  • Classification: hydrolase inhibitor
  • Organism(s): Ixodes ricinus
  • Expression System: Escherichia coli

  • Deposited: 2017-05-26 Released: 2018-06-13 
  • Deposition Author(s): Busa, M., Rezacova, P., Kotal, J., Kotsyfakis, M., Mares, M.
  • Funding Organization(s): Czech Science Foundation; Ministry of Education, Youth and Sports of the Czech Republic; INSTITUTE OF ORGANIC CHEMISTRY AND BIOCHEMISTRY AS CR V.V.I.; Institute of Parasitology, the Czech Academy of Sciences; Grant Agency of the University of South Bohemia in Ceske Budejovice; European Union 

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.76 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.191 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The structure and function of Iristatin, a novel immunosuppressive tick salivary cystatin.

Kotal, J.Stergiou, N.Busa, M.Chlastakova, A.Berankova, Z.Rezacova, P.Langhansova, H.Schwarz, A.Calvo, E.Kopecky, J.Mares, M.Schmitt, E.Chmelar, J.Kotsyfakis, M.

(2019) Cell.Mol.Life Sci. 76: 2003-2013

  • DOI: 10.1007/s00018-019-03034-3

  • PubMed Abstract: 
  • To successfully feed, ticks inject pharmacoactive molecules into the vertebrate host including cystatin cysteine protease inhibitors. However, the molecular and cellular events modulated by tick saliva remain largely unknown. Here, we describe and ch ...

    To successfully feed, ticks inject pharmacoactive molecules into the vertebrate host including cystatin cysteine protease inhibitors. However, the molecular and cellular events modulated by tick saliva remain largely unknown. Here, we describe and characterize a novel immunomodulatory cystatin, Iristatin, which is upregulated in the salivary glands of feeding Ixodes ricinus ticks. We present the crystal structure of Iristatin at 1.76 Å resolution. Purified recombinant Iristatin inhibited the proteolytic activity of cathepsins L and C and diminished IL-2, IL-4, IL-9, and IFN-γ production by different T-cell populations, IL-6 and IL-9 production by mast cells, and nitric oxide production by macrophages. Furthermore, Iristatin inhibited OVA antigen-induced CD4 + T-cell proliferation and leukocyte recruitment in vivo and in vitro. Our results indicate that Iristatin affects wide range of anti-tick immune responses in the vertebrate host and may be exploitable as an immunotherapeutic.


    Organizational Affiliation

    Laboratory of Genomics and Proteomics of Disease Vectors, Biology Centre CAS, Institute of Parasitology, Branišovská 1160/31, 37005, České Budějovice, Czech Republic. mich_kotsyfakis@yahoo.com.,Laboratory of Genomics and Proteomics of Disease Vectors, Biology Centre CAS, Institute of Parasitology, Branišovská 1160/31, 37005, České Budějovice, Czech Republic.,Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA.,Department of Medical Biology, Faculty of Science, University of South Bohemia in České Budějovice, Branišovská 1760c, 37005, České Budějovice, Czech Republic.,Institute for Immunology, University Medical Center of the Johannes Gutenberg-University Mainz, Langenbeckstrasse 1, Mainz, 55131, Germany.,Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610, Prague, Czech Republic.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Iristatin
B, A
120Ixodes ricinusMutation(s): 0 
Find proteins for A0A3B6UEB6 (Ixodes ricinus)
Go to UniProtKB:  A0A3B6UEB6
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.76 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.191 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 39.033α = 90.00
b = 76.929β = 90.00
c = 92.122γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
XDSdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Czech Science FoundationCzech Republic13-11043S
Ministry of Education, Youth and Sports of the Czech RepublicCzech RepublicInterBioMed LO1302
INSTITUTE OF ORGANIC CHEMISTRY AND BIOCHEMISTRY AS CR V.V.I.Czech RepublicRVO 61388963
Institute of Parasitology, the Czech Academy of SciencesCzech RepublicRVO 60077344
Czech Science FoundationCzech RepublicP502/12/2409
Grant Agency of the University of South Bohemia in Ceske BudejoviceCzech Republic038/2016/P
European UnionMarie Curie Reintegration grant PIRG07-GA-2010-268177

Revision History 

  • Version 1.0: 2018-06-13
    Type: Initial release
  • Version 1.1: 2019-06-26
    Type: Data collection, Database references