1E03

PLASMA ALPHA ANTITHROMBIN-III AND PENTASACCHARIDE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.90 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.199 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 2.1 of the entry. See complete history


Literature

Structure of Beta-Antithrombin and the Effect of Glycosylation on Antithrombin'S Heparin Affinity and Activity.

Mccoy, A.J.Pei, X.Y.Skinner, R.Abrahams, J.-P.Carrell, R.W.

(2003) J Mol Biol 326: 823

  • DOI: https://doi.org/10.1016/s0022-2836(02)01382-7
  • Primary Citation of Related Structures:  
    1E03, 1E04, 1E05

  • PubMed Abstract: 

    Antithrombin is a member of the serpin family of protease inhibitors and the major inhibitor of the blood coagulation cascade. It is unique amongst the serpins in that it circulates in a conformation that is inactive against its target proteases. Activation of antithrombin is brought about by a conformational change initiated upon binding heparin or heparan sulphate. Two isoforms exist in the circulation, alpha-antithrombin and beta-antithrombin, which differ in the amount of glycosylation present on the polypeptide chain; beta-antithrombin lacks the carbohydrate present at Asn135 in alpha-antithrombin. Of the two forms, beta-antithrombin has the higher affinity for heparin and thus functions as the major inhibitor in vivo even though it is the less abundant form. The reason for the differences in heparin affinity between the alpha and beta-forms have been shown to be due to the additional carbohydrate changing the rate of the conformational change. Here, we describe the most accurate structures of alpha-antithrombin and alpha-antithrombin+heparin pentasaccharide reported to date (2.6A and 2.9A resolution, respectively, both re-refinements using old data), and the structure of beta-antithrombin (2.6A resolution). The new structures have a remarkable degree of ordered carbohydrate and include parts of the antithrombin chain not modeled before. The structures have allowed a detailed comparison of the conformational differences between the three. They show that the structural basis of the lower affinity for heparin of alpha-antithrombin over beta-antithrombin is due to the conformational change that occurs upon heparin binding being sterically hindered by the presence of the additional bulky carbohydrate at Asn135.


  • Organizational Affiliation

    Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, UK.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
ANTITHROMBIN-IIIA [auth I],
B [auth L]
432Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P01008 (Homo sapiens)
Explore P01008 
Go to UniProtKB:  P01008
PHAROS:  P01008
GTEx:  ENSG00000117601 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01008
Glycosylation
Glycosylation Sites: 3Go to GlyGen: P01008-1
Sequence Annotations
Expand
  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranoseC [auth A]2N-Glycosylation
Glycosylation Resources
GlyTouCan:  G42666HT
GlyCosmos:  G42666HT
GlyGen:  G42666HT
Entity ID: 3
MoleculeChains Length2D Diagram Glycosylation3D Interactions
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranoseD [auth B],
E [auth C],
F [auth D]
3N-Glycosylation
Glycosylation Resources
GlyTouCan:  G15407YE
GlyCosmos:  G15407YE
GlyGen:  G15407YE
Entity ID: 4
MoleculeChains Length2D Diagram Glycosylation3D Interactions
3,4-di-O-methyl-2,6-di-O-sulfo-alpha-D-glucopyranose-(1-4)-2,3-di-O-methyl-beta-D-glucopyranuronic acid-(1-4)-2,3,6-tri-O-sulfo-alpha-D-glucopyranose-(1-4)-3-O-methyl-2-O-sulfo-alpha-L-idopyranuronic acid-(1-4)-methyl 2,3,6-tri-O-sulfo-alpha-D-glucopyranosideG [auth E],
H [auth F]
5N/A
Glycosylation Resources
GlyTouCan:  G76630SM
GlyCosmos:  G76630SM
Small Molecules
Biologically Interesting Molecules (External Reference) 1 Unique
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.90 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.199 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 70.511α = 90
b = 87.071β = 108.88
c = 97.349γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
AMoREphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-06-02
    Type: Initial release
  • Version 1.1: 2011-05-07
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Advisory, Atomic model, Data collection, Derived calculations, Non-polymer description, Other, Structure summary
  • Version 2.1: 2023-12-06
    Changes: Data collection, Database references, Refinement description, Structure summary