1fgx: Difference between revisions

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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 with as ligand. Active as Beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase, with EC number 2.4.1.38 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

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-[[Image:1fgx.gif|left|200px]]<br /><applet load="1fgx" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1fgx.gif|left|200px]]<br /><applet load="1fgx" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1fgx, resolution 2.4&Aring;" />
 '''CRYSTAL STRUCTURE OF THE BOVINE BETA 1,4 GALACTOSYLTRANSFERASE (B4GALT1) CATALYTIC DOMAIN COMPLEXED WITH UMP'''<br />
 ==Overview==
-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.
+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 Structure==
-FGX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with U5P as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [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] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1FGX OCA].
+FGX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=U5P:'>U5P</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [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] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FGX OCA].
 ==Reference==
@@ Line 16: / Line 16: @@
 [[Category: Bourne, Y.]]
 [[Category: Cambillau, C.]]
-[[Category: Gastinel, L.N.]]
+[[Category: Gastinel, L N.]]
 [[Category: U5P]]
 [[Category: alpha beta alpha fold]]
 [[Category: nucleotide binding protein]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 14:55:00 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:38:33 2008''