Biological Assembly 1  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 assigned by authors.

Biological Assembly 3  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 3 assigned by authors.

Macromolecule Content

• Total Structure Weight: 96.43 kDa 
• Atom Count: 6463 
• Residue Count: 770 
• Unique protein chains: 1

1AXM

HEPARIN-LINKED BIOLOGICALLY-ACTIVE DIMER OF FIBROBLAST GROWTH FACTOR

• DOI: 10.2210/pdb1AXM/pdb

• Classification: GROWTH FACTOR
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 1997-10-16 Released: 1998-04-22 
• Deposition Author(s): DiGabriele, A.D., Lax, I., Chen, D.I., Svahn, C.M., Jaye, M., Schlessinger, J., Hendrickson, W.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.304 
• R-Value Work: 0.217 
• R-Value Observed: 0.217 

Literature

Structure of a heparin-linked biologically active dimer of fibroblast growth factor.

DiGabriele, A.D., Lax, I., Chen, D.I., Svahn, C.M., Jaye, M., Schlessinger, J., Hendrickson, W.A.

(1998) Nature 393: 812-817

• PubMed: 9655399 
• DOI: 10.1038/31741
• Primary Citation of Related Structures:  
  1AXM, 2AXM


• PubMed Abstract: 
  

The fibroblast growth factors (FGFs) form a large family of structurally related, multifunctional proteins that regulate various biological responses. They mediate cellular functions by binding to transmembrane FGF receptors, which are protein tyrosine kinases. FGF receptors are activated by oligomerization, and both this activation and FGF-stimulated biological responses require heparin-like molecules as well as FGF. Heparins are linear anionic polysaccharide chains; they are typically heterogeneously sulphated on alternating L-iduronic and D-glucosamino sugars, and are nearly ubiquitous in animal tissues as heparan sulphate proteoglycans on cell surfaces and in the extracellular matrix. Although several crystal structures have been described for FGF molecules in complexes with heparin-like sugars, the nature of a biologically active complex has been unknown until now. Here we describe the X-ray crystal structure, at 2.9 A resolution, of a biologically active dimer of human acidic FGF in a complex with a fully sulphated, homogeneous heparin decassacharide. The dimerization of heparin-linked acidic FGF observed here is an elegant mechanism for the modulation of signalling through combinatorial homodimerization and heterodimerization of the 12 known members of the FGF family.

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Related Citations: 

• X-ray crystal structure of human acidic fibroblast growth factor.
  Blaber, M., DiSalvo, J., Thomas, K.A.
  (1996) Biochemistry 35: 2086

• Heparin Structure and Interactions with Basic Fibroblast Growth Factor
  Faham, S., Hileman, R.E., Fromm, J.R., Linhardt, R.J., Rees, D.C.
  (1996) Science 271: 1116

• Structural Studies of the Binding of the Anti-Ulcer Drug Sucrose Octasulfate to Acidic Fibroblast Growth Factor
  Zhu, X., Hsu, B.T., Rees, D.C.
  (1993) Structure 1: 27

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ACIDIC FIBROBLAST GROWTH FACTOR	A, B, C, D, E, F	135	Homo sapiens	Mutation(s): 1  Gene Names: ECGF, FGF1, FGFA
Find proteins for P05230 (Homo sapiens) Explore P05230  Go to UniProtKB:  P05230
NIH Common Fund Data Resources
PHAROS  P05230 GTEx  ENSG00000113578

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
2-deoxy-6-O-sulfo-2-(sulfoamino)-alpha-D-glucopyranose-(1-4)-2-O-sulfo-alpha-L-idopyranuronic acid-(1-4)-2-deoxy-6-O-sulfo-2-(sulfoamino)-alpha-D-glucopyranose-(1-4)-2-O-sulfo-alpha-L-idopyranuronic acid-(1-4)-2-deoxy-6-O-sulfo-2-(sulfoamino)-alpha-D-glucopyranose	G, H	5		N/A

Entity ID: 3
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
2-O-sulfo-alpha-L-idopyranuronic acid-(1-4)-2-deoxy-6-O-sulfo-2-(sulfoamino)-alpha-D-glucopyranose-(1-4)-2-O-sulfo-alpha-L-idopyranuronic acid-(1-4)-2-deoxy-6-O-sulfo-2-(sulfoamino)-alpha-D-glucopyranose-(1-4)-2-O-sulfo-alpha-L-idopyranuronic acid	I	5		N/A

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A,B,C,D,E,F	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.304 
• R-Value Work: 0.217 
• R-Value Observed: 0.217 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 87.69	α = 90
b = 158.05	β = 90
c = 190.58	γ = 90

Software Package:

Software Name	Purpose
MADSYS	phasing
X-PLOR	refinement
DENZO	data reduction
CCP4	data scaling
ROTAVATA	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1997-10-16 
• Released Date: 1998-04-22 
Deposition Author(s): DiGabriele, A.D., Lax, I., Chen, D.I., Svahn, C.M., Jaye, M., Schlessinger, J., Hendrickson, W.A.

Revision History 

• Version 1.0: 1998-04-22
  Type: Initial release
  
• Version 1.1: 2008-03-25
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Non-polymer description, Version format compliance
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Refinement description, Structure summary