Biological Assembly 1  

 3D View: Structure

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: 48.06 kDa 
• Atom Count: 3966 
• Residue Count: 441 
• Unique protein chains: 2

1OPG

OPG2 FAB FRAGMENT

• DOI: 10.2210/pdb1OPG/pdb

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


• Deposited: 1995-04-28 Released: 1995-07-31 
• Deposition Author(s): Kodandapani, R., Veerapandian, B., Ely, K.R.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Observed: 0.160 

Literature

Crystal structure of the OPG2 Fab. An antireceptor antibody that mimics an RGD cell adhesion site.

Kodandapani, R., Veerapandian, B., Kunicki, T.J., Ely, K.R.

(1995) J Biol Chem 270: 2268-2273

• PubMed: 7836460 
• DOI: 10.1074/jbc.270.5.2268
• Primary Citation of Related Structures:  
  1OPG


• PubMed Abstract: 
  

Cell surface receptors called integrins mediate diverse cell adhesion phenomena through recognition of the sequence arginine-glycine-aspartic acid (RGD) present in proteins such as fibronectin and fibrinogen. Platelet aggregation in hemostasis is mediated by the binding of fibrinogen to the gpIIb/IIIa integrin. The OPG2 antibody binds the gpIIb/IIIa receptor and acts as a ligand mimic due to the presence of an arginine-tyrosine-aspartic acid (RYD) sequence in the CDR3 loop of the heavy chain. The RYD loop and side chains are ordered in the 2.0-A resolution crystal structure of the Fab fragment from this antireceptor antibody. Moreover, the RYD loop assumes two clearly defined conformations that may correspond to the orientations of the loop in the free state or bound to integrin. This molecule will serve as a tool for understanding protein-integrin recognition in platelet aggregation and other RGD-mediated cell adhesion interactions.

---

Related Citations: 

• Crystallization of Opg2 Fab Fragment: A Fibrinogen Mimic with Specificity for the Platelet Glycoprotein
  Celikel, R., Williamson, M.M., Kunicki, T.J., Ely, K.R.
  (1992) Acta Crystallogr D Biol Crystallogr 49: 421

---

Organizational Affiliation: 

Cancer Research Center, La Jolla Cancer Research Foundation, California 92037.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
OPG2 FAB (LIGHT CHAIN)	L	214	Homo sapiens	Mutation(s): 0

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
OPG2 FAB (HEAVY CHAIN)	H	227	Homo sapiens	Mutation(s): 0
Find proteins for P01868 (Mus musculus) Explore P01868  Go to UniProtKB:  P01868

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Observed: 0.160 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 93.1	α = 90
b = 83.8	β = 90
c = 53.7	γ = 90

Software Package:

Software Name	Purpose
HOWARD	data collection
A.J.	data collection
NILSEN	data collection
C.	data collection
PROLSQ	refinement
XENGEN	data reduction
NIELSEN	data reduction
XUONG)	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1995-04-28 
• Released Date: 1995-07-31 
Deposition Author(s): Kodandapani, R., Veerapandian, B., Ely, K.R.

Revision History 

• Version 1.0: 1995-07-31
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance