1BM3: Immunoglobulin Opg2 Fab-peptide Complex

Citation:
Abstract
Antibodies are important tools to explore receptor-ligand interactions. The anti-integrin antibody OPG2 binds in an RGD-related manner to the alphaIIb beta3 integrin as a molecular mimic of fibrinogen. The Fab fragment from OPG2 was cocrystallized with a peptide from the beta3 subunit of the integrin representing a site that binds RGD. The crystal structure of the complex was determined at 2.2-A resolution and compared with the unbound Fab. On binding the integrin peptide there were conformational changes in CDR3 of the heavy chain. Also, a significant shift across the intermolecular interface between the CH1-CL domains was observed so that the angle of rotation relating the two domains was reduced by 15 degrees. This unusual conformational adjustment represents the first example of ligand-induced conformational changes in the carboxyl domains of a Fab fragment.
PDB ID: 1BM3Download
MMDB ID: 10161
PDB Deposition Date: 1999/4/15
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 2  Å
Source Organism:
Similar Structures:
Biological Unit for 1BM3: dimeric; determined by author and by software (PISA)
Molecular Components in 1BM3
Label Count Molecule
Proteins (2 molecules)
1
Immunoglobulin Opg2 Fab, Constant Domain
Molecule annotation
1
Immunoglobulin Opg2 Fab, Variable Domain
Molecule annotation
* Click molecule labels to explore molecular sequence information.

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