1gx4: Difference between revisions

Revision as of 18:07, 2 May 2008

ALPHA-,1,3 GALACTOSYLTRANSFERASE- N-ACETYL LACTOSAMINE COMPLEX

OverviewOverview

Bovine alpha-1,3-galactosyltransferase (alpha3GT) catalyzes the synthesis of the alpha-galactose (alpha-Gal) epitope, the target of natural human antibodies. It represents a family of enzymes, including the histo blood group A and B transferases, that catalyze retaining glycosyltransfer reactions of unknown mechanism. An initial study of alpha3GT in a crystal form with limited resolution and considerable disorder suggested the possible formation of a beta-galactosyl-enzyme covalent intermediate (Gastinel, L. N., Bignon, C., Misra, A. K., Hindsgaul, O., Shaper, J. H., and Joziasse, D. H. (2001) EMBO J. 20, 638-649). Highly ordered structures are described for complexes of alpha3GT with donor substrate, UDP-galactose, UDP- glucose, and two acceptor substrates, lactose and N-acetyllactosamine, at resolutions up to 1.46 A. Structural and calorimetric binding studies suggest an obligatory ordered binding of donor and acceptor substrates, linked to a donor substrate-induced conformational change, and the direct participation of UDP in acceptor binding. The monosaccharide-UDP bond is cleaved in the structures containing UDP-galactose and UDP-glucose, producing non-covalent complexes containing buried beta-galactose and alpha-glucose. The location of these monosaccharides and molecular modeling suggest that binding of a distorted conformation of UDP-galactose may be important in the catalytic mechanism of alpha3GT.

About this StructureAbout this Structure

1GX4 is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.

ReferenceReference

Structural basis of ordered binding of donor and acceptor substrates to the retaining glycosyltransferase, alpha-1,3-galactosyltransferase., Boix E, Zhang Y, Swaminathan GJ, Brew K, Acharya KR, J Biol Chem. 2002 Aug 2;277(31):28310-8. Epub 2002 May 14. PMID:12011052 Page seeded by OCA on Fri May 2 18:07:43 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
 [[Image:1gx4.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1gx4 |SIZE=350|CAPTION= <scene name='initialview01'>1gx4</scene>, resolution 1.46&Aring;
+The line below this paragraph, containing "STRUCTURE_1gx4", creates the "Structure Box" on the page.
-|SITE= <scene name='pdbsite=AC1:Nag+Binding+Site+For+Chain+B'>AC1</scene>
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=UDP:URIDINE-5&#39;-DIPHOSPHATE'>UDP</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/N-acetyllactosaminide_3-alpha-galactosyltransferase N-acetyllactosaminide 3-alpha-galactosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.87 2.4.1.87] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE=
+-->
-|DOMAIN=
+{{STRUCTURE_1gx4|  PDB=1gx4  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1gx4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gx4 OCA], [http://www.ebi.ac.uk/pdbsum/1gx4 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1gx4 RCSB]</span>
-}}
 '''ALPHA-,1,3 GALACTOSYLTRANSFERASE- N-ACETYL LACTOSAMINE COMPLEX'''
@@ Line 31: / Line 28: @@
 [[Category: Swaminathan, G J.]]
 [[Category: Zhang, Y.]]
-[[Category: blood group sugar]]
+[[Category: Blood group sugar]]
-[[Category: galactosyltransferase]]
+[[Category: Galactosyltransferase]]
-[[Category: glycosyltransferase]]
+[[Category: Glycosyltransferase]]
-[[Category: lactose]]
+[[Category: Lactose]]
-[[Category: n-acetyl lactosamine]]
+[[Category: N-acetyl lactosamine]]
-[[Category: transferase]]
+[[Category: Transferase]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 18:07:43 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 20:53:07 2008''