View source for 3f0p


==Crystal structure of the mercury-bound form of MerB, the Organomercurial Lyase involved in a bacterial mercury resistance system==
<StructureSection load='3f0p' size='340' side='right'caption='[[3f0p]], [[Resolution|resolution]] 1.64&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3f0p]] is a 2 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=3F0P OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3F0P 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]] 1.64&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BR:BROMIDE+ION'>BR</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</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=3f0p FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3f0p OCA], [https://pdbe.org/3f0p PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3f0p RCSB], [https://www.ebi.ac.uk/pdbsum/3f0p PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3f0p ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MERB_ECOLX MERB_ECOLX] Cleaves the carbon-mercury bond of organomercurials such as phenylmercuric acetate. One product is Hg(2+), which is subsequently detoxified by the mercuric reductase (By similarity).
== 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/f0/3f0p_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=3f0p ConSurf].
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== Publication Abstract from PubMed ==
Bacteria resistant to methylmercury utilize two enzymes (MerA and MerB) to degrade methylmercury to the less toxic elemental mercury. The crucial step is the cleavage of the carbon-mercury bond of methylmercury by the organomercurial lyase (MerB). In this study, we determined high resolution crystal structures of MerB in both the free (1.76-A resolution) and mercury-bound (1.64-A resolution) states. The crystal structure of free MerB is very similar to the NMR structure, but important differences are observed when comparing the two structures. In the crystal structure, an amino-terminal alpha-helix that is not present in the NMR structure makes contact with the core region adjacent to the catalytic site. This interaction between the amino-terminal helix and the core serves to bury the active site of MerB. The crystal structures also provide detailed insights into the mechanism of carbon-mercury bond cleavage by MerB. The structures demonstrate that two conserved cysteines (Cys-96 and Cys-159) play a role in substrate binding, carbon-mercury bond cleavage, and controlled product (ionic mercury) release. In addition, the structures establish that an aspartic acid (Asp-99) in the active site plays a crucial role in the proton transfer step required for the cleavage of the carbon-mercury bond. These findings are an important step in understanding the mechanism of carbon-mercury bond cleavage by MerB.

Crystal structures of the organomercurial lyase MerB in its free and mercury-bound forms: insights into the mechanism of methylmercury degradation.,Lafrance-Vanasse J, Lefebvre M, Di Lello P, Sygusch J, Omichinski JG J Biol Chem. 2009 Jan 9;284(2):938-44. Epub 2008 Nov 12. PMID:19004822<ref>PMID:19004822</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 3f0p" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Di Lello P]]
[[Category: Lafrance-Vanasse J]]
[[Category: Lefebvre M]]
[[Category: Omichinski JG]]
[[Category: Sygusch J]]