ISDA

Deposition Date 2007-03-08

Release Date 2007-04-10

Last Version Date 2024-11-13

Entry Detail

PDB ID:

2UUY

Keywords:

HYDROLASE

Title:

Structure of a tick tryptase inhibitor in complex with bovine trypsin

Biological Source:

Source Organism:

BOS TAURUS (Taxon ID: 9913)
RHIPICEPHALUS APPENDICULATUS (Taxon ID: 34631)

Method Details:

Experimental Method:

X-RAY DIFFRACTION

Resolution:

1.15 Å

R-Value Free:

0.16

R-Value Work:

0.13

R-Value Observed:

0.13

Space Group:

P 21 21 21

Download Validation Report

Macromolecular Entities

Protein Blast

Polymer Type:polypeptide(L)
Molecule:CATIONIC TRYPSIN
Gene (Uniprot):PRSS1
Chain IDs:A
Chain Length:223
Number of Molecules:1
Biological Source:BOS TAURUS

UniProt ID:P00760 Pfam ID:PF00089 EC:3.4.21.4

Protein Blast

Polymer Type:polypeptide(L)
Molecule:TRYPTASE INHIBITOR
Chain IDs:B
Chain Length:52
Number of Molecules:1
Biological Source:RHIPICEPHALUS APPENDICULATUS

UniProt ID:Q1EG59

Ligand Molecules

Primary Citation

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.Show

J.Mol.Biol. 368 1172 ? (2007)

PMID: 17391695 DOI: 10.1016/J.JMB.2007.03.011

Abstact

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.

Legend

Protein

Chemical

Disease

Primary Citation of related structures