5TJK image
Deposition Date 2016-10-04
Release Date 2017-06-14
Last Version Date 2023-10-04
Entry Detail
PDB ID:
5TJK
Keywords:
Title:
Crystal structure of GTA + A trisaccharide (native)
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Host Organism:
Method Details:
Experimental Method:
Resolution:
1.45 Å
R-Value Free:
0.19
R-Value Work:
0.18
R-Value Observed:
0.18
Space Group:
C 2 2 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Histo-blood group ABO system transferase
Gene (Uniprot):ABO
Chain IDs:A
Chain Length:297
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation
High-resolution crystal structures and STD NMR mapping of human ABO(H) blood group glycosyltransferases in complex with trisaccharide reaction products suggest a molecular basis for product release.
Glycobiology 27 966 977 (2017)
PMID: 28575295 DOI: 10.1093/glycob/cwx053

Abstact

The human ABO(H) blood group A- and B-synthesizing glycosyltransferases GTA and GTB have been structurally characterized to high resolution in complex with their respective trisaccharide antigen products. These findings are particularly timely and relevant given the dearth of glycosyltransferase structures collected in complex with their saccharide reaction products. GTA and GTB utilize the same acceptor substrates, oligosaccharides terminating with α-l-Fucp-(1→2)-β-d-Galp-OR (where R is a glycolipid or glycoprotein), but use distinct UDP donor sugars, UDP-N-acetylgalactosamine and UDP-galactose, to generate the blood group A (α-l-Fucp-(1→2)[α-d-GalNAcp-(1→3)]-β-d-Galp-OR) and blood group B (α-l-Fucp-(1→2)[α-d-Galp-(1→3)]-β-d-Galp-OR) determinant structures, respectively. Structures of GTA and GTB in complex with their respective trisaccharide products reveal a conflict between the transferred sugar monosaccharide and the β-phosphate of the UDP donor. Mapping of the binding epitopes by saturation transfer difference NMR measurements yielded data consistent with the X-ray structural results. Taken together these data suggest a mechanism of product release where monosaccharide transfer to the H-antigen acceptor induces active site disorder and ejection of the UDP leaving group prior to trisaccharide egress.

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Primary Citation of related structures