1IDO

I-DOMAIN FROM INTEGRIN CR3, MG2+ BOUND

• PDB DOI: https://doi.org/10.2210/pdb1IDO/pdb

• Classification: CELL ADHESION PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1996-03-12 Released: 1996-08-01 
• Deposition Author(s): Lee, J.-O., Liddington, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Work: 0.202 
• R-Value Observed: 0.202 

Literature

Crystal structure of the A domain from the alpha subunit of integrin CR3 (CD11b/CD18).

Lee, J.O., Rieu, P., Arnaout, M.A., Liddington, R.

(1995) Cell 80: 631-638

• PubMed: 7867070 
• DOI: https://doi.org/10.1016/0092-8674(95)90517-0
• Primary Citation of Related Structures:  
  1IDO


• PubMed Abstract: 
  

  We have determined the high resolution crystal structure of the A domain from the alpha chain of integrin CR3. The domain adopts a classic alpha/beta "Rossmann" fold and contains an unusual Mg2+ coordination site at its surface. One of the coordinating ligands is the glutamate side chain from another A domain molecule. We suggest that this site represents a general metal ion-dependent adhesion site (MIDAS) for binding protein ligands. We further propose that the beta subunits of integrins contain a MIDAS motif within a modified A domain. Our crystal structure will allow reliable models to be built for other members of the A domain superfamily and should facilitate development of novel adhesion modulatory drugs.

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Organizational Affiliation: 

Laboratory of X-Ray Crystallography, Dana Farber Cancer Institute, Harvard Medical School Boston, Massachusetts 02115.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 21.69 kDa 
• Atom Count: 1,632 
• Modelled Residue Count: 184 
• Deposited Residue Count: 189 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INTEGRIN	A	189	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P11215 (Homo sapiens) Explore P11215  Go to UniProtKB:  P11215
PHAROS:  P11215 GTEx:  ENSG00000169896

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MG	B [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Work: 0.202 
• R-Value Observed: 0.202 
• Space Group: P 4₃

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 45.7	α = 90
b = 45.7	β = 90
c = 94.3	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1996-08-01 
Deposition Author(s): Lee, J.-O., Liddington, R.

Revision History  

• Version 1.0: 1996-08-01
  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: 2018-03-21
  Changes: Data collection, Other
• Version 1.4: 2024-02-07
  Changes: Data collection, Database references, Derived calculations