1COU

ANTICOAGULANT PROTEIN FROM THE NEMATODE ANCYLOSTOMA CANINUM


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 18 
  • Selection Criteria: LEAST RESTRAINT VIOLATIONS AND LOWEST ENERGIES 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Inherent flexibility in a potent inhibitor of blood coagulation, recombinant nematode anticoagulant protein c2.

Duggan, B.M.Dyson, H.J.Wright, P.E.

(1999) Eur.J.Biochem. 265: 539-548


  • PubMed Abstract: 
  • Nematode anticoagulant proteins (NAPs) from the hematophagous nematode Ancylostoma caninum inhibit blood coagulation with picomolar inhibition constants, and have been targeted as novel pharmaceutical agents. NAP5 and NAP6 inhibit factor Xa by bindin ...

    Nematode anticoagulant proteins (NAPs) from the hematophagous nematode Ancylostoma caninum inhibit blood coagulation with picomolar inhibition constants, and have been targeted as novel pharmaceutical agents. NAP5 and NAP6 inhibit factor Xa by binding to its active site, whereas NAPc2 binds to factor Xa at a different, as yet unidentified, site and the resultant binary complex inhibits the tissue factor-factor VIIa complex. We have undertaken NMR studies of NAPc2, including the calculation of a solution structure, and found that the protein is folded, with five disulfide bonds, but is extremely flexible, especially in the acidic loop. The Halpha secondary shifts and 3JHNHalpha coupling constants indicate the presence of some beta structure and a short helix, but the intervening loops are highly conformationally heterogeneous. Heteronuclear NOE measurements showed the presence of large amplitude motions on a subnanosecond timescale at the N-terminus and C-terminus and in the substrate-binding loop, indicating that the conformational heterogeneity observed in the NMR structures is due to flexibility of the polypeptide chain in these regions. Flexibility may well be an important factor in the physiological function of NAPc2, because it must interact with other proteins in the inhibition of blood coagulation. We suggest that this inhibitor is likely to become structured on binding to factor Xa, because the inhibition of the tissue factor-factor VIIa complex requires both NAPc2 and factor Xa.


    Related Citations: 
    • Anticoagulant Repertoire of the Hookworm Ancylostoma Caninum
      Stanssens, P.,Bergum, P.W.,Gansemans, Y.,Jespers, L.,Laroche, Y.,Huang, S.,Maki, S.,Messens, J.,Lauwereys, M.,Cappello, M.,Hotez, P.J.,Lasters, I.,Vlasuk, G.P.
      (1996) Proc.Natl.Acad.Sci.USA 93: 2149


    Organizational Affiliation

    Department of Molecular Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (NEMATODE ANTICOAGULANT PROTEIN C2)
A
85Ancylostoma caninumMutation(s): 0 
Find proteins for Q16938 (Ancylostoma caninum)
Go to UniProtKB:  Q16938
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 18 
  • Selection Criteria: LEAST RESTRAINT VIOLATIONS AND LOWEST ENERGIES 
  • Olderado: 1COU Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-10-20
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance