1JVQ

Crystal structure at 2.6A of the ternary complex between antithrombin, a P14-P8 reactive loop peptide, and an exogenous tetrapeptide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.204 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

How small peptides block and reverse serpin polymerisation

Zhou, A.Stein, P.E.Huntington, J.A.Sivasothy, P.Lomas, D.A.Carrell, R.W.

(2004) J.Mol.Biol. 342: 931-941

  • DOI: 10.1016/j.jmb.2004.07.078

  • PubMed Abstract: 
  • Many of the late-onset dementias, including Alzheimer's disease and the prion encephalopathies, arise from the aberrant aggregation of individual proteins. The serpin family of serine protease inhibitors provides a well-defined structural example of ...

    Many of the late-onset dementias, including Alzheimer's disease and the prion encephalopathies, arise from the aberrant aggregation of individual proteins. The serpin family of serine protease inhibitors provides a well-defined structural example of such pathological aggregation, as its mutant variants readily form long-chain polymers, resulting in diseases ranging from thrombosis to dementia. The intermolecular linkages result from the insertion of the reactive site loop of one serpin molecule into the middle strand (s4A) position of the A beta-sheet of another molecule. We define here the structural requirements for small peptides to competitively bind to and block the s4A position to prevent this intermolecular linkage and polymerisation. The entry and anchoring of blocking-peptides is facilitated by the presence of a threonine which inserts into the site equivalent to P8 of s4A. But the critical requirement for small blocking-peptides is demonstrated in crystallographic structures of the complexes formed with selected tri- and tetrapeptides. These structures indicate that the binding is primarily due to the insertion of peptide hydrophobic side-chains into the P4 and P6 sites of s4A. The findings allow the rational design of synthetic blocking-peptides small enough to be suitable for mimetic design. This is demonstrated here with a tetrapeptide that preferentially blocks the polymerisation of a pathologically unstable serpin commonly present in people of European descent.


    Organizational Affiliation

    Departments of Haematology and Medicine, University of Cambridge, Cambridge Institute for Medical Research, Hills Road, Cambridge CB2 2XY, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ANTITHROMBIN-III
L, I
432Homo sapiensMutation(s): 0 
Gene Names: SERPINC1 (AT3)
Find proteins for P01008 (Homo sapiens)
Go to Gene View: SERPINC1
Go to UniProtKB:  P01008
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
P14-P8 reactive loop peptide
C
8N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
exogenous Cholecystokinin tetrapeptide
D
5N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NDG
Query on NDG

Download SDF File 
Download CCD File 
I, L
2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE
C8 H15 N O6
OVRNDRQMDRJTHS-PVFLNQBWSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
I
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Modified Residues  2 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
D
NON-POLYMERH2 N

--

ACE
Query on ACE
C
NON-POLYMERC2 H4 O

--

Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.204 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 69.144α = 90.00
b = 100.622β = 104.42
c = 87.157γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
TRUNCATEdata reduction
CCP4data scaling
MOSFLMdata reduction
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-06-03
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary, Version format compliance