View source for 1guq

==STRUCTURE OF NUCLEOTIDYLTRANSFERASE COMPLEXED WITH UDP-GLUCOSE==
<StructureSection load='1guq' size='340' side='right' caption='[[1guq]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1guq]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GUQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1GUQ FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=UPG:URIDINE-5-DIPHOSPHATE-GLUCOSE'>UPG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/UTP--hexose-1-phosphate_uridylyltransferase UTP--hexose-1-phosphate uridylyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.10 2.7.7.10] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1guq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1guq OCA], [http://pdbe.org/1guq PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1guq RCSB], [http://www.ebi.ac.uk/pdbsum/1guq PDBsum]</span></td></tr>
</table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/gu/1guq_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1guq ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Galactose-1-phosphate uridylyltransferase plays a key role in galactose metabolism by catalyzing the transfer of a uridine 5'-phosphoryl group from UDP-glucose to galactose 1-phosphate. The enzyme from Escherichia coli is composed of two identical subunits. The structures of the enzyme/UDP-glucose and UDP-galactose complexes, in which the catalytic nucleophile His 166 has been replaced with a glycine residue, have been determined and refined to 1.8 A resolution by single crystal X-ray diffraction analysis. Crystals employed in the investigation belonged to the space group P2(1) with unit cell dimensions of a = 68 A, b = 58 A, c = 189 A, and beta = 100 degrees and two dimers in the asymmetric unit. The models for these enzyme/substrate complexes have demonstrated that the active site of the uridylyltransferase is formed by amino acid residues contributed from both subunits in the dimer. Those amino acid residues critically involved in sugar binding include Asn 153 and Gly 159 from the first subunit and Lys 311, Phe 312, Val 314, Tyr 316, Glu 317, and Gln 323 from the second subunit. The uridylyltransferase is able to accommodate both UDP-galactose and UDP-glucose substrates by simple movements of the side chains of Glu 317 and Gln 323 and by a change in the backbone dihedral angles of Val 314. The removal of the imidazole group at position 166 results in little structural perturbation of the polypeptide chain backbone when compared to the previously determined structure for the wild-type enzyme. Instead, the cavity created by the mutation is partially compensated for by the presence of a potassium ion and its accompanying coordination sphere. As such, the mutant protein structures presented here represent valid models for understanding substrate recognition and binding in the native galactose-1-phosphate uridylyltransferase.

Structural analysis of the H166G site-directed mutant of galactose-1-phosphate uridylyltransferase complexed with either UDP-glucose or UDP-galactose: detailed description of the nucleotide sugar binding site.,Thoden JB, Ruzicka FJ, Frey PA, Rayment I, Holden HM Biochemistry. 1997 Feb 11;36(6):1212-22. PMID:9063869<ref>PMID:9063869</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1guq" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus coli migula 1895]]
[[Category: UTP--hexose-1-phosphate uridylyltransferase]]
[[Category: Holden, H]]
[[Category: Rayment, I]]
[[Category: Thoden, J B]]
[[Category: Galactose metabolism]]
[[Category: Nucleotidyltransferase]]
[[Category: Transferase]]