Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 6.08 kDa 
• Atom Count: 449 
• Modelled Residue Count: 51 
• Deposited Residue Count: 55 
• Unique protein chains: 1

 1BX7

HIRUSTASIN FROM HIRUDO MEDICINALIS AT 1.2 ANGSTROMS

• PDB DOI: 10.2210/pdb1BX7/pdb

• Classification: ANTI-COAGULANT
• Organism(s): Hirudo medicinalis
• Expression System: Saccharomyces cerevisiae
• Mutation(s): No 


• Deposited: 1998-10-14 Released: 1999-04-27 
• Deposition Author(s): Uson, I., Sheldrick, G.M., De La Fortelle, E., Bricogne, G., Di Marco, S., Priestle, J.P., Gruetter, M.G., Mittl, P.R.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.225 
• R-Value Observed: 0.179 

Literature

The 1.2 A crystal structure of hirustasin reveals the intrinsic flexibility of a family of highly disulphide-bridged inhibitors.

Uson, I., Sheldrick, G.M., de La Fortelle, E., Bricogne, G., Di Marco, S., Priestle, J.P., Grutter, M.G., Mittl, P.R.

(1999) Structure 7: 55-63

• PubMed: 10368273 
• DOI: 10.1016/s0969-2126(99)80009-4
• Primary Citation of Related Structures:  
  1BX7, 1BX8


• PubMed Abstract: 
  

Leech-derived inhibitors have a prominent role in the development of new antithrombotic drugs, because some of them are able to block the blood coagulation cascade. Hirustasin, a serine protease inhibitor from the leech Hirudo medicinalis, binds specifically to tissue kallikrein and possesses structural similarity with antistasin, a potent factor Xa inhibitor from Haementeria officinalis. Although the 2.4 A structure of the hirustasin-kallikrein complex is known, classical methods such as molecular replacement were not successful in solving the structure of free hirustasin.

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Related Citations: 

• A New Structural Class of Serine Protease Inhibitors Revealed by the Structure of the Hirustasin-Kallikrein Complex
  Mittl, P.R., Di Marco, S., Fendrich, G., Pohlig, G., Heim, J., Sommerhoff, C., Fritz, H., Priestle, J.P., Grutter, M.G.
  (1997) Structure 5: 253

• Erratum. A New Structural Class of Serine Protease Inhibitors Revealed by the Structure of the Hirustasin-Kallikrein Complex
  Mittl, P.R., Di Marco, S., Fendrich, G., Pohlig, G., Heim, J., Sommerhoff, C., Fritz, H., Priestle, J.P., Grutter, M.G.
  (1997) Structure 5: 585

• Recombinant Hirustasin: Production in Yeast, Crystallization, and Interaction with Serine Proteases
  Di Marco, S., Fendrich, G., Knecht, R., Strauss, A., Pohlig, G., Heim, J., Priestle, J.P., Sommerhoff, C.P., Grutter, M.G.
  (1997) Protein Sci 6: 109

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Organizational Affiliation: 

Institut für Anorganische Chemie der Universität, Tammannstrasse 4, D-37077 Göttingen, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HIRUSTASIN	A	55	Hirudo medicinalis	Mutation(s): 0
UniProt
Find proteins for P80302 (Hirudo medicinalis) Explore P80302  Go to UniProtKB:  P80302

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	B [auth A], C [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.225 
• R-Value Observed: 0.179 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 37.713	α = 90
b = 37.713	β = 90
c = 67.812	γ = 90

Software Package:

Software Name	Purpose
MARXDS	data collection
MARSCALE	data reduction
SHELXL-97	model building
SHELXL-97	refinement
MARXDS	data reduction
MARSCALE	data scaling
SHELXL-97	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1999-04-27 
Deposition Author(s): Uson, I., Sheldrick, G.M., De La Fortelle, E., Bricogne, G., Di Marco, S., Priestle, J.P., Gruetter, M.G., Mittl, P.R.E.

Revision History  

• Version 1.0: 1999-04-27
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance