Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 35.59 kDa 
• Atom Count: 2601 
• Modelled Residue Count: 281 
• Deposited Residue Count: 298 
• Unique protein chains: 3

2H9T

Crystal structure of human alpha-thrombin in complex with suramin

• PDB DOI: 10.2210/pdb2H9T/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 2006-06-11 Released: 2007-05-22 
• Deposition Author(s): Lima, L.M.T.R., Polikarpov, I., Monteiro, R.Q.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.266 
• R-Value Work: 0.180 
• R-Value Observed: 0.184 

Literature

Structural and thermodynamic analysis of thrombin:suramin interaction in solution and crystal phases.

Lima, L.M., Becker, C.F., Giesel, G.M., Marques, A.F., Cargnelutti, M.T., de Oliveira Neto, M., Queiroz Monteiro, R., Verli, H., Polikarpov, I.

(2009) Biochim Biophys Acta 1794: 873-881

• PubMed: 19332154 
• DOI: 10.1016/j.bbapap.2009.03.011
• Primary Citation of Related Structures:  
  2H9T, 3BF6


• PubMed Abstract: 
  

Suramin is a hexasulfonated naphthylurea which has been recently characterized as a non-competitive inhibitor of human alpha-thrombin activity over fibrinogen, although its binding site and mode of interaction with the enzyme remain elusive. Here, we determined two X-ray structure of the thrombin:suramin complex, refined at 2.4 A resolution. While a single thrombin:suramin complex was found in the asymmetric unit cell of the crystal, some of the crystallographic contacts with symmetrically related molecules are mediated by both the enzyme and the ligand. Molecular dynamics simulations with the 1:1 complex demonstrate a large rearrangement of suramin in the complex, but with the protein scaffold and the more extensive protein-ligand regions keep unchanged. Small-angle X-ray scattering measurements at high micromolar concentration demonstrate a suramin-induced dimerization of the enzyme. These data indicating a dissimilar binding mode in the monomeric and oligomeric states, with a monomeric, 1:1 complex to be more likely to exist at the thrombin physiological, nanomolar concentration range. Collectively, close understanding on the structural basis for interaction is given which might establish a basis for design of suramin analogues targeting thrombin.

---

Organizational Affiliation: 

Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, 21941-590, Rio de Janeiro, RJ, Brazil. [e-mail]

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Thrombin	A [auth L]	36	Homo sapiens	Mutation(s): 0  Gene Names: F2 EC: 3.4.21.5
UniProt & NIH Common Fund Data Resources
Find proteins for P00734 (Homo sapiens) Explore P00734  Go to UniProtKB:  P00734
PHAROS:  P00734 GTEx:  ENSG00000180210

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Thrombin	B [auth H]	259	Homo sapiens	Mutation(s): 0  Gene Names: F2 EC: 3.4.21.5
UniProt & NIH Common Fund Data Resources
Find proteins for P00734 (Homo sapiens) Explore P00734  Go to UniProtKB:  P00734
PHAROS:  P00734 GTEx:  ENSG00000180210

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
PPACK active site thrombin inhibitor	C [auth I]	3	N/A	Mutation(s): 0

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SVR	D [auth H]	8,8'-[CARBONYLBIS[IMINO-3,1-PHENYLENECARBONYLIMINO(4-METHYL-3,1-PHENYLENE)CARBONYLIMINO]]BIS-1,3,5-NAPHTHALENETRISULFON IC ACID C51 H40 N6 O23 S6 FIAFUQMPZJWCLV-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
SVR	PDBBind:  2H9T	IC50: 2.00e+4 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.266 
• R-Value Work: 0.180 
• R-Value Observed: 0.184 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 43.966	α = 90
b = 76.202	β = 90
c = 113.848	γ = 90

Software Package:

Software Name	Purpose
SCALA	data scaling
MOLREP	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-06-11 
• Released Date: 2007-05-22 
Deposition Author(s): Lima, L.M.T.R., Polikarpov, I., Monteiro, R.Q.

Revision History  

• Version 1.0: 2007-05-22
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance