1S3K image
Deposition Date 2004-01-13
Release Date 2004-07-13
Last Version Date 2024-10-30
Entry Detail
PDB ID:
1S3K
Keywords:
IMMUNE SYSTEM
Title:
Crystal Structure of a Humanized Fab (hu3S193) in Complex with the Lewis Y Tetrasaccharide
Biological Source:
Source Organism:
Mus musculus (Taxon ID: 10090)
Host Organism:
Mus musculus
Method Details:
Experimental Method:
X-RAY DIFFRACTION
Resolution:
1.90 Å
R-Value Free:
0.23
R-Value Work:
0.20
R-Value Observed:
0.20
Space Group:
P 31
1S3K validation report
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:HU3S193 Fab fragment, heavy chain
Chain IDs:B (auth: H)
Chain Length:222
Number of Molecules:1
Biological Source:Mus musculus
Polymer Type:polypeptide(L)
Molecule:HU3S193 Fab fragment, light chain
Chain IDs:A (auth: L)
Chain Length:219
Number of Molecules:1
Biological Source:Mus musculus
Ligand Molecules
GOL
Peptide-like Molecules
PRD_900124
Primary Citation
Structural convergence of antibody binding of carbohydrate determinants in lewis y tumor antigens
J.Mol.Biol. 340 809 818 (2004)
PMID: 15223322 DOI: 10.1016/j.jmb.2004.05.037

Abstact

Antibodies targeting human epithelial carcinomas bearing Lewis Y (Le(y)) carbohydrate antigens provide a striking illustration of convergent immune recognition. We report a 1.9A resolution crystal structure of the Fab of a humanized antibody (hu3S193) in complex with the Le(y) tetrasaccharide, Fuc(alpha 1-->2)Gal(beta 1-->4)[Fuc(alpha 1-->3)]GlcNAc. Comparisons of the hu3S193 and BR96 antibodies bound to Le(y) tumor antigens revealed extremely similar mechanisms for recognition of the carbohydrate epitopes. Solvent plays a critical role in hu3S193 antibody binding to the Le(y) carbohydrate epitope. Specificity for Le(y) is maintained because a conserved pocket accepts an N-acetyl group of the core Gal(beta 1-->4)GlcNAc disaccharide. Closely related blood-group determinants (Le(a) and Le(b)) cannot enter the specificity pocket, making the Le(y) antibodies promising candidates for immunotherapy of epithelial cancer.

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Chemical

Disease

Primary Citation of related structures
1S3K