1R81

Glycosyltransferase A in complex with 3-amino-acceptor analog inhibitor and uridine diphosphate-N-acetyl-galactose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.214 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The influence of an intramolecular hydrogen bond in differential recognition of inhibitory acceptor analogs by human ABO(H) blood group A and B glycosyltransferases

Nguyen, H.P.Seto, N.O.L.Cai, Y.Leinala, E.K.Borisova, S.N.Palcic, M.M.Evans, S.V.

(2003) J.Biol.Chem. 278: 49191-49195

  • DOI: 10.1074/jbc.M308770200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Human ABO(H) blood group glycosyltransferases GTA and GTB catalyze the final monosaccharide addition in the biosynthesis of the human A and B blood group antigens. GTA and GTB utilize a common acceptor, the H antigen disaccharide alpha-l-Fucp-(1-->2) ...

    Human ABO(H) blood group glycosyltransferases GTA and GTB catalyze the final monosaccharide addition in the biosynthesis of the human A and B blood group antigens. GTA and GTB utilize a common acceptor, the H antigen disaccharide alpha-l-Fucp-(1-->2)-beta-d-Galp-OR, but different donors, where GTA transfers GalNAc from UDP-GalNAc and GTB transfers Gal from UDP-Gal. GTA and GTB are two of the most homologous enzymes known to transfer different donors and differ in only 4 amino acid residues, but one in particular (Leu/Met-266) has been shown to dominate the selection between donor sugars. The structures of the A and B glycosyltransferases have been determined to high resolution in complex with two inhibitory acceptor analogs alpha-l-Fucp(1-->2)-beta-d-(3-deoxy)-Galp-OR and alpha-l-Fucp-(1-->2)-beta-d-(3-amino)-Galp-OR, in which the 3-hydroxyl moiety of the Gal ring has been replaced by hydrogen or an amino group, respectively. Remarkably, although the 3-deoxy inhibitor occupies the same conformation and position observed for the native H antigen in GTA and GTB, the 3-amino analog is recognized differently by the two enzymes. The 3-amino substitution introduces a novel intramolecular hydrogen bond between O2' on Fuc and N3' on Gal, which alters the minimum-energy conformation of the inhibitor. In the absence of UDP, the 3-amino analog can be accommodated by either GTA or GTB with the l-Fuc residue partially occupying the vacant UDP binding site. However, in the presence of UDP, the analog is forced to abandon the intramolecular hydrogen bond, and the l-Fuc residue is shifted to a less ordered conformation. Further, the residue Leu/Met-266 that was thought important only in distinguishing between donor substrates is observed to interact differently with the 3-amino acceptor analog in GTA and GTB. These observations explain why the 3-deoxy analog acts as a competitive inhibitor of the glycosyltransferase reaction, whereas the 3-amino analog displays complex modes of inhibition.


    Related Citations: 
    • Crystallography & NMR System
      Brunger, A.T.,Adams, P.D.,Clore, G.M.,Delano, W.L.,Gros, P.,Grosse-Kunstleve, R.,Jiang, J.-S.,Kuszewski, J.,Nilges, M.,Pannu, N.S.,Read, R.J.,Rice, L.M.,Simonson, T.,Warren, G.
      (1998) Acta Crystallogr.,Sect.D 54: 905


    Organizational Affiliation

    Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Glycoprotein-fucosylgalactoside alpha-N-acetylgalactosaminyltransferase
A
283Homo sapiensMutation(s): 0 
Gene Names: ABO
Find proteins for P16442 (Homo sapiens)
Go to Gene View: ABO
Go to UniProtKB:  P16442
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
AIG
Query on AIG

Download SDF File 
Download CCD File 
A
4-AMINO-2-HEXYLOXY-6-HYDROXYMETHYL-TETRAHYDRO-PYRAN-3,5-DIOL
C12 H25 N O5
MSXUDXAZMKOOST-YBXAARCKSA-N
 Ligand Interaction
FUC
Query on FUC

Download SDF File 
Download CCD File 
A
ALPHA-L-FUCOSE
C6 H12 O5
SHZGCJCMOBCMKK-SXUWKVJYSA-N
 Ligand Interaction
UD2
Query on UD2

Download SDF File 
Download CCD File 
A
URIDINE-DIPHOSPHATE-N-ACETYLGALACTOSAMINE
(2R,3R,4R,5R,6R)-3-(acetylamino)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl [(2R,3S,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl dihydrogen diphosphate
C17 H27 N3 O17 P2
LFTYTUAZOPRMMI-NESSUJCYSA-N
 Ligand Interaction
HG
Query on HG

Download SDF File 
Download CCD File 
A
MERCURY (II) ION
Hg
BQPIGGFYSBELGY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.214 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 52.600α = 90.00
b = 149.400β = 90.00
c = 79.700γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
CNSphasing
CNSrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-02-10
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance