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| - | [[Image:4znb.jpg|left|200px]] | |
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| - | {{Structure
| + | ==METALLO-BETA-LACTAMASE (C181S MUTANT)== |
| - | |PDB= 4znb |SIZE=350|CAPTION= <scene name='initialview01'>4znb</scene>, resolution 2.65Å
| + | <StructureSection load='4znb' size='340' side='right'caption='[[4znb]], [[Resolution|resolution]] 2.65Å' scene=''> |
| - | |SITE= <scene name='pdbsite=NAA:Deduced+From+The+Coordination.+Na+Was+Present+In+The+Cry+...'>NAA</scene>, <scene name='pdbsite=NAB:Deduced+From+The+Coordination.+Na+Was+Present+In+The+Cry+...'>NAB</scene>, <scene name='pdbsite=ZNA:Only+The+Zn1+Site+Of+Binuclear+Zn+Center+Is+Occupied'>ZNA</scene> and <scene name='pdbsite=ZNB:Only+The+Zn1+Site+Of+Binuclear+Zn+Center+Is+Occupied'>ZNB</scene>
| + | == Structural highlights == |
| - | |LIGAND= <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> | + | <table><tr><td colspan='2'>[[4znb]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacteroides_fragilis Bacteroides fragilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZNB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4ZNB FirstGlance]. <br> |
| - | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] </span>
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.65Å</td></tr> |
| - | |GENE= CCRA3 (WITHOUT SIGNAL SEQUENCE ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=817 Bacteroides fragilis])
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> |
| - | |DOMAIN=
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4znb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4znb OCA], [https://pdbe.org/4znb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4znb RCSB], [https://www.ebi.ac.uk/pdbsum/4znb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4znb ProSAT]</span></td></tr> |
| - | |RELATEDENTRY= | + | </table> |
| - | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4znb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4znb OCA], [http://www.ebi.ac.uk/pdbsum/4znb PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=4znb RCSB]</span> | + | == Function == |
| - | }}
| + | [https://www.uniprot.org/uniprot/BLAB_BACFG BLAB_BACFG] Can hydrolyze carbapenem compounds. |
| | + | == 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/zn/4znb_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=4znb ConSurf]. |
| | + | <div style="clear:both"></div> |
| | | | |
| - | '''METALLO-BETA-LACTAMASE (C181S MUTANT)'''
| + | ==See Also== |
| - | | + | *[[Beta-lactamase 3D structures|Beta-lactamase 3D structures]] |
| - | | + | __TOC__ |
| - | ==Overview== | + | </StructureSection> |
| - | The metallo-beta-lactamases require divalent cations such as zinc or cadmium for hydrolyzing the amide bond of beta-lactam antibiotics. The crystal structure of the Zn2+ -bound enzyme from Bacteroides fragilis contains a binuclear zinc center in the active site. A hydroxide, coordinated to both zinc atoms, is proposed as the moiety that mounts the nucleophilic attack on the carbonyl carbon atom of the beta-lactam bond of the substrate. It was previously reported that the replacement of the active site Cys181 by a serine residue severely impaired catalysis while atomic absorption measurements indicated that binding of the two zinc ions remained intact. Contradicting data emerge from recent mass spectrometry results, which show that only a single zinc ion binds to the C181S metallo-beta-lactamase. In the current study, the C181S mutant enzyme was examined at the atomic level by determining the crystal structure at 2.6 A resolution. The overall structure of the mutant enzyme is the same as that of the wild-type enzyme. At the mutation site, the side chain of Ser181 occupies the same position as that of the side chain of Cys181 in the wild-type protein. One zinc ion, Zn1, is present in the crystal structure; however, the site of the second zinc ion, Zn2 is unoccupied. A water molecule is associated with Zn1, reminiscent of the hydroxide seen in the structure of the wild-type enzyme but farther from the metal. The position of the water molecule is off the plane of the carboxylate group of Asp103; therefore, the water molecule may be less nucleophilic than a water molecule which is coplanar with the carboxylate group.
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| - | | + | |
| - | ==About this Structure==
| + | |
| - | 4ZNB is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacteroides_fragilis Bacteroides fragilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZNB OCA].
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| - | | + | |
| - | ==Reference==
| + | |
| - | Structural consequences of the active site substitution Cys181 ==> Ser in metallo-beta-lactamase from Bacteroides fragilis., Li Z, Rasmussen BA, Herzberg O, Protein Sci. 1999 Jan;8(1):249-52. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10210203 10210203]
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| | [[Category: Bacteroides fragilis]] | | [[Category: Bacteroides fragilis]] |
| - | [[Category: Beta-lactamase]] | + | [[Category: Large Structures]] |
| - | [[Category: Single protein]]
| + | [[Category: Herzberg O]] |
| - | [[Category: Herzberg, O.]] | + | [[Category: Li Z]] |
| - | [[Category: Li, Z.]] | + | |
| - | [[Category: beta-lactamase]]
| + | |
| - | [[Category: cadmium]]
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| - | [[Category: hydrolase]]
| + | |
| - | [[Category: metallo beta-lactamase]]
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| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 05:40:47 2008''
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