View source for 1jz5


==E. COLI (lacZ) BETA-GALACTOSIDASE IN COMPLEX WITH D-GALCTOPYRANOSYL-1-ON==
<StructureSection load='1jz5' size='340' side='right'caption='[[1jz5]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1jz5]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JZ5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1JZ5 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=149:D-GALACTONOLACTONE'>149</scene>, <scene name='pdbligand=DMS:DIMETHYL+SULFOXIDE'>DMS</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1jz5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jz5 OCA], [https://pdbe.org/1jz5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1jz5 RCSB], [https://www.ebi.ac.uk/pdbsum/1jz5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1jz5 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/BGAL_ECOLI BGAL_ECOLI] 
== 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/jz/1jz5_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=1jz5 ConSurf].
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== Publication Abstract from PubMed ==
The structures of a series of complexes designed to mimic intermediates along the reaction coordinate for beta-galactosidase are presented. These complexes clarify and enhance previous proposals regarding the catalytic mechanism. The nucleophile, Glu537, is seen to covalently bind to the galactosyl moiety. Of the two potential acids, Mg(2+) and Glu461, the latter is in better position to directly assist in leaving group departure, suggesting that the metal ion acts in a secondary role. A sodium ion plays a part in substrate binding by directly ligating the galactosyl 6-hydroxyl. The proposed reaction coordinate involves the movement of the galactosyl moiety deep into the active site pocket. For those ligands that do bind deeply there is an associated conformational change in which residues within loop 794-804 move up to 10 A closer to the site of binding. In some cases this can be inhibited by the binding of additional ligands. The resulting restricted access to the intermediate helps to explain why allolactose, the natural inducer for the lac operon, is the preferred product of transglycosylation.

A structural view of the action of Escherichia coli (lacZ) beta-galactosidase.,Juers DH, Heightman TD, Vasella A, McCarter JD, Mackenzie L, Withers SG, Matthews BW Biochemistry. 2001 Dec 11;40(49):14781-94. PMID:11732897<ref>PMID:11732897</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1jz5" style="background-color:#fffaf0;"></div>

==See Also==
*[[Galactosidase 3D structures|Galactosidase 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Juers DH]]
[[Category: Matthews BW]]