2UUX

Structure of the tryptase inhibitor TdPI from a tick


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.40 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.171 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

A Tick Protein with a Modified Kunitz Fold Inhibits Human Tryptase.

Paesen, G.C.Siebold, C.Harlos, K.Peacey, M.F.Nuttall, P.A.Stuart, D.I.

(2007) J Mol Biol 368: 1172

  • DOI: https://doi.org/10.1016/j.jmb.2007.03.011
  • Primary Citation of Related Structures:  
    2UUX, 2UUY

  • PubMed Abstract: 

    TdPI, a tick salivary gland product related to Kunitz/BPTI proteins is a potent inhibitor of human beta-tryptase. Kinetic assays suggest that three of the four catalytic sites of tryptase are blocked by TdPI, and that the inhibition of one of these involves a peptide flanking the Kunitz head. In the course of the inhibition, tryptase cleaves TdPI at several positions. Crystal structures of the TdPI head, on its own and in complex with trypsin, reveal features that are not found in classical Kunitz/BPTI proteins and suggest the mode of interaction with tryptase. The loop of TdPI connecting the beta-sheet with the C-terminal alpha-helix is shortened, the disulphide-bridge pattern altered and N and C termini separated to produce a highly pointed molecule capable of penetrating the cramped active sites of tryptase. TdPI accumulates in the cytosolic granules of mast cells, presumably suppressing inflammation in the host animal's skin by tryptase inhibition.


  • Organizational Affiliation

    CEH, Mansfield Road, Oxford, OX1 3SR, UK. gcp@ceh.ac.uk


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
TRYPTASE INHIBITOR55Rhipicephalus appendiculatusMutation(s): 0 
UniProt
Find proteins for Q1EG59 (Rhipicephalus appendiculatus)
Explore Q1EG59 
Go to UniProtKB:  Q1EG59
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ1EG59
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.40 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.171 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 53.676α = 90
b = 28.594β = 90
c = 30.11γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
SHELXphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-04-03
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance