1fgx: Difference between revisions

Revision as of 16:18, 2 May 2008

CRYSTAL STRUCTURE OF THE BOVINE BETA 1,4 GALACTOSYLTRANSFERASE (B4GALT1) CATALYTIC DOMAIN COMPLEXED WITH UMP

OverviewOverview

beta1,4-galactosyltransferase T1 (beta4Gal-T1, EC 2.4.1.90/38), a Golgi resident membrane-bound enzyme, transfers galactose from uridine diphosphogalactose to the terminal beta-N-acetylglucosamine residues forming the poly-N-acetyllactosamine core structures present in glycoproteins and glycosphingolipids. In mammals, beta4Gal-T1 binds to alpha-lactalbumin, a protein that is structurally homologous to lyzozyme, to produce lactose. beta4Gal-T1 is a member of a large family of homologous beta4galactosyltransferases that use different types of glycoproteins and glycolipids as substrates. Here we solved and refined the crystal structures of recombinant bovine beta4Gal-T1 to 2.4 A resolution in the presence and absence of the substrate uridine diphosphogalactose. The crystal structure of the bovine substrate-free beta4Gal-T1 catalytic domain showed a new fold consisting of a single conical domain with a large open pocket at its base. In the substrate-bound complex, the pocket encompassed residues interacting with uridine diphosphogalactose. The structure of the complex contained clear regions of electron density for the uridine diphosphate portion of the substrate, where its beta-phosphate group was stabilized by hydrogen-bonding contacts with conserved residues including the Asp252ValAsp254 motif. These results help the interpretation of engineered beta4Gal-T1 point mutations. They suggest a mechanism possibly involved in galactose transfer and enable identification of the critical amino acids involved in alpha-lactalbumin interactions.

About this StructureAbout this Structure

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

ReferenceReference

Crystal structures of the bovine beta4galactosyltransferase catalytic domain and its complex with uridine diphosphogalactose., Gastinel LN, Cambillau C, Bourne Y, EMBO J. 1999 Jul 1;18(13):3546-57. PMID:10393171 Page seeded by OCA on Fri May 2 16:18:48 2008

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

OCA

@@ Line 1: / Line 1: @@
 [[Image:1fgx.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1fgx |SIZE=350|CAPTION= <scene name='initialview01'>1fgx</scene>, resolution 2.4&Aring;
+The line below this paragraph, containing "STRUCTURE_1fgx", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=U5P:URIDINE-5&#39;-MONOPHOSPHATE'>U5P</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/Beta-N-acetylglucosaminylglycopeptide_beta-1,4-galactosyltransferase Beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.38 2.4.1.38] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE=
+-->
-|DOMAIN=
+{{STRUCTURE_1fgx|  PDB=1fgx  |  SCENE=  }}
-|RELATEDENTRY=[[1fr8|1FR8]]
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1fgx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fgx OCA], [http://www.ebi.ac.uk/pdbsum/1fgx PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1fgx RCSB]</span>
-}}
 '''CRYSTAL STRUCTURE OF THE BOVINE BETA 1,4 GALACTOSYLTRANSFERASE (B4GALT1) CATALYTIC DOMAIN COMPLEXED WITH UMP'''
@@ Line 29: / Line 26: @@
 [[Category: Cambillau, C.]]
 [[Category: Gastinel, L N.]]
-[[Category: alpha beta alpha fold]]
+[[Category: Alpha beta alpha fold]]
-[[Category: nucleotide binding protein]]
+[[Category: Nucleotide binding protein]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 16:18:48 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 20:22:40 2008''