3H5C

X-Ray Structure of Protein Z-Protein Z Inhibitor Complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.26 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Basis for the specificity and activation of the serpin protein Z-dependent proteinase inhibitor (ZPI) as an inhibitor of membrane-associated factor Xa.

Huang, X.Dementiev, A.Olson, S.T.Gettins, P.G.

(2010) J.Biol.Chem. 285: 20399-20409

  • DOI: 10.1074/jbc.M110.112748

  • PubMed Abstract: 
  • The serpin ZPI is a protein Z (PZ)-dependent specific inhibitor of membrane-associated factor Xa (fXa) despite having an unfavorable P1 Tyr. PZ accelerates the inhibition reaction approximately 2000-fold in the presence of phospholipid and Ca(2+). To ...

    The serpin ZPI is a protein Z (PZ)-dependent specific inhibitor of membrane-associated factor Xa (fXa) despite having an unfavorable P1 Tyr. PZ accelerates the inhibition reaction approximately 2000-fold in the presence of phospholipid and Ca(2+). To elucidate the role of PZ, we determined the x-ray structure of Gla-domainless PZ (PZ(DeltaGD)) complexed with protein Z-dependent proteinase inhibitor (ZPI). The PZ pseudocatalytic domain bound ZPI at a novel site through ionic and polar interactions. Mutation of four ZPI contact residues eliminated PZ binding and membrane-dependent PZ acceleration of fXa inhibition. Modeling of the ternary Michaelis complex implicated ZPI residues Glu-313 and Glu-383 in fXa binding. Mutagenesis established that only Glu-313 is important, contributing approximately 5-10-fold to rate acceleration of fXa and fXIa inhibition. Limited conformational change in ZPI resulted from PZ binding, which contributed only approximately 2-fold to rate enhancement. Instead, template bridging from membrane association, together with previously demonstrated interaction of the fXa and ZPI Gla domains, resulted in an additional approximately 1000-fold rate enhancement. To understand why ZPI has P1 tyrosine, we examined a P1 Arg variant. This reacted at a diffusion-limited rate with fXa, even without PZ, and predominantly as substrate, reflecting both rapid acylation and deacylation. P1 tyrosine thus ensures that reaction with fXa or most other arginine-specific proteinases is insignificant unless PZ binds and localizes ZPI and fXa on the membrane, where the combined effects of Gla-Gla interaction, template bridging, and interaction of fXa with Glu-313 overcome the unfavorability of P1 Tyr and ensure a high rate of reaction as an inhibitor.


    Organizational Affiliation

    Center for Molecular Biology of Oral Diseases, University of Illinois at Chicago, Chicago, Illinois 60607, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein Z-dependent protease inhibitor
A
423Homo sapiensMutation(s): 0 
Gene Names: SERPINA10 (ZPI)
Find proteins for Q9UK55 (Homo sapiens)
Go to Gene View: SERPINA10
Go to UniProtKB:  Q9UK55
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Vitamin K-dependent protein Z
B
317Homo sapiensMutation(s): 0 
Gene Names: PROZ
Find proteins for P22891 (Homo sapiens)
Go to Gene View: PROZ
Go to UniProtKB:  P22891
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BGC
Query on BGC

Download SDF File 
Download CCD File 
B
BETA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.26 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.201 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 119.934α = 90.00
b = 119.934β = 90.00
c = 347.672γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
PHASERphasing
XDSdata scaling
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-04-28
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-11-01
    Type: Refinement description