1ILT

X-RAY STRUCTURE OF INTERLEUKIN-1 RECEPTOR ANTAGONIST AT 2.0 ANGSTROMS RESOLUTION

• PDB DOI: https://doi.org/10.2210/pdb1ILT/pdb

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


• Deposited: 1994-03-09 Released: 1995-04-01 
• Deposition Author(s): Brandhuber, B.J., Vigers, G.P.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.236 
• R-Value Observed: 0.236 

Literature

X-ray structure of interleukin-1 receptor antagonist at 2.0-A resolution.

Vigers, G.P., Caffes, P., Evans, R.J., Thompson, R.C., Eisenberg, S.P., Brandhuber, B.J.

(1994) J Biol Chem 269: 12874-12879

• PubMed: 8175703 
• Primary Citation of Related Structures:  
  1ILT


• PubMed Abstract: 
  

  Interleukin-1 receptor antagonist (IL-1ra) is a natural competitive antagonist of IL-1. In order to further elucidate the mechanism by which IL-1ra binds without activating the IL-1 receptor, we have solved the crystal structure of IL-1ra at 2.0-A resolution. IL-1ra has the same overall beta-trefoil fold as IL-1 alpha and IL-1 beta and has a very similar hydrophobic core. However, there are a number of structural differences between the molecules, including significant differences at the open end of the beta-barrel, which has been identified in IL-1 beta as a receptor binding site.

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Organizational Affiliation: 

Synergen, Inc., Boulder, Colorado 80301.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

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

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 34.29 kDa 
• Atom Count: 286 
• Modelled Residue Count: 286 
• Deposited Residue Count: 304 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INTERLEUKIN-1 RECEPTOR ANTAGONIST	A, B	152	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P18510 (Homo sapiens) Explore P18510  Go to UniProtKB:  P18510
PHAROS:  P18510 GTEx:  ENSG00000136689

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.236 
• R-Value Observed: 0.236 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 71.11	α = 90
b = 71.11	β = 90
c = 112.61	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1995-04-01 
Deposition Author(s): Brandhuber, B.J., Vigers, G.P.A.

Revision History  

• Version 1.0: 1995-04-01
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2017-11-29
  Changes: Derived calculations, Other
• Version 1.4: 2024-02-07
  Changes: Data collection, Database references