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1xpb

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[[Image:1xpb.gif|left|200px]]<br /><applet load="1xpb" size="350" color="white" frame="true" align="right" spinBox="true"
 
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caption="1xpb, resolution 1.90&Aring;" />
 
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'''STRUCTURE OF BETA-LACTAMASE TEM1'''<br />
 
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==Overview==
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==STRUCTURE OF BETA-LACTAMASE TEM1==
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beta-Lactamases are bacterial enzymes which catalyse the hydrolysis of the, beta-lactam ring of penicillins, cephalosporins and related compounds, thus inactivating these antibiotics. The crystal structure of the TEM1, beta-lactamase has been determined at 1.9 A resolution by the, molecular-replacement method, using the atomic coordinates of two, homologous beta-lactamase refined structures which show about 36% strict, identity in their amino-acid sequences and 1.96 A r.m.s. deviation between, equivalent Calpha atoms. The TEM1 enzyme crystallizes in space group, P2(1)2(1)2(1) and there is one molecule per asymmetric unit. The structure, was refined by simulated annealing to an R-factor of 15.6% for 15 086, reflections with I &gt;/= 2sigma(I) in the resolution range 5.0-1.9 A. The, final crystallographic structure contains 263 amino-acid residues, one, sulfate anion in the catalytic cleft and 135 water molecules per, asymmetric unit. The folding is very similar to that of the other known, class A beta-lactamases. It consists of two domains, the first is formed, by a five-stranded beta-sheet covered by three alpha-helices on one face, and one alpha-helix on the other, the second domain contains mainly, alpha-helices. The catalytic cleft is located at the interface between the, two domains. We also report the crystallographic study of the TEM S235A, mutant. This mutation of an active-site residue specifically decreases the, acylation rate of cephalosporins. This TEM S235A mutant crystallizes under, the same conditions as the wild-type protein and its structure was refined, at 2.0 A resolution with an R value of 17.6%. The major modification is, the appearance of a water molecule near the mutated residue, which is, incompatible with the OG 235 present in the wild-type enzyme, and causes, very small perturbations in the interaction network in the active site.
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<StructureSection load='1xpb' size='340' side='right'caption='[[1xpb]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
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== Structural highlights ==
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<table><tr><td colspan='2'>[[1xpb]] is a 1 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=1XPB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1XPB FirstGlance]. <br>
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</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.9&#8491;</td></tr>
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<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
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<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1xpb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xpb OCA], [https://pdbe.org/1xpb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1xpb RCSB], [https://www.ebi.ac.uk/pdbsum/1xpb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1xpb ProSAT]</span></td></tr>
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</table>
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== Function ==
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[https://www.uniprot.org/uniprot/BLAT_ECOLX BLAT_ECOLX] TEM-type are the most prevalent beta-lactamases in enterobacteria; they hydrolyze the beta-lactam bond in susceptible beta-lactam antibiotics, thus conferring resistance to penicillins and cephalosporins. TEM-3 and TEM-4 are capable of hydrolyzing cefotaxime and ceftazidime. TEM-5 is capable of hydrolyzing ceftazidime. TEM-6 is capable of hydrolyzing ceftazidime and aztreonam. TEM-8/CAZ-2, TEM-16/CAZ-7 and TEM-24/CAZ-6 are markedly active against ceftazidime. IRT-4 shows resistance to beta-lactamase inhibitors.
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== Evolutionary Conservation ==
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[[Image:Consurf_key_small.gif|200px|right]]
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Check<jmol>
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<jmolCheckbox>
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<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/xp/1xpb_consurf.spt"</scriptWhenChecked>
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<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
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<text>to colour the structure by Evolutionary Conservation</text>
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</jmolCheckbox>
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</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=1xpb ConSurf].
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<div style="clear:both"></div>
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<div style="background-color:#fffaf0;">
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== Publication Abstract from PubMed ==
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beta-Lactamases are bacterial enzymes which catalyse the hydrolysis of the beta-lactam ring of penicillins, cephalosporins and related compounds, thus inactivating these antibiotics. The crystal structure of the TEM1 beta-lactamase has been determined at 1.9 A resolution by the molecular-replacement method, using the atomic coordinates of two homologous beta-lactamase refined structures which show about 36% strict identity in their amino-acid sequences and 1.96 A r.m.s. deviation between equivalent Calpha atoms. The TEM1 enzyme crystallizes in space group P2(1)2(1)2(1) and there is one molecule per asymmetric unit. The structure was refined by simulated annealing to an R-factor of 15.6% for 15 086 reflections with I &gt;/= 2sigma(I) in the resolution range 5.0-1.9 A. The final crystallographic structure contains 263 amino-acid residues, one sulfate anion in the catalytic cleft and 135 water molecules per asymmetric unit. The folding is very similar to that of the other known class A beta-lactamases. It consists of two domains, the first is formed by a five-stranded beta-sheet covered by three alpha-helices on one face and one alpha-helix on the other, the second domain contains mainly alpha-helices. The catalytic cleft is located at the interface between the two domains. We also report the crystallographic study of the TEM S235A mutant. This mutation of an active-site residue specifically decreases the acylation rate of cephalosporins. This TEM S235A mutant crystallizes under the same conditions as the wild-type protein and its structure was refined at 2.0 A resolution with an R value of 17.6%. The major modification is the appearance of a water molecule near the mutated residue, which is incompatible with the OG 235 present in the wild-type enzyme, and causes very small perturbations in the interaction network in the active site.
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==About this Structure==
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TEM1 beta-lactamase structure solved by molecular replacement and refined structure of the S235A mutant.,Fonze E, Charlier P, To'th Y, Vermeire M, Raquet X, Dubus A, Frere JM Acta Crystallogr D Biol Crystallogr. 1995 Sep 1;51(Pt 5):682-94. PMID:15299797<ref>PMID:15299797</ref>
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1XPB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [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] Known structural/functional Site: <scene name='pdbsite=ACT:Active+Site'>ACT</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XPB OCA].
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==Reference==
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From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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TEM1 beta-lactamase structure solved by molecular replacement and refined structure of the S235A mutant., Fonze E, Charlier P, To'th Y, Vermeire M, Raquet X, Dubus A, Frere JM, Acta Crystallogr D Biol Crystallogr. 1995 Sep 1;51(Pt 5):682-94. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15299797 15299797]
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</div>
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[[Category: Beta-lactamase]]
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<div class="pdbe-citations 1xpb" style="background-color:#fffaf0;"></div>
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[[Category: Escherichia coli]]
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[[Category: Single protein]]
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[[Category: Charlier, P.]]
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[[Category: Fonze, E.]]
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[[Category: SO4]]
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[[Category: antibiotic resistance]]
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[[Category: hydrolase]]
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[[Category: signal]]
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[[Category: transposable element]]
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''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 10:22:08 2008''
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==See Also==
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*[[Beta-lactamase 3D structures|Beta-lactamase 3D structures]]
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== References ==
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<references/>
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__TOC__
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</StructureSection>
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[[Category: Escherichia coli]]
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[[Category: Large Structures]]
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[[Category: Charlier P]]
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[[Category: Fonze E]]

Current revision

STRUCTURE OF BETA-LACTAMASE TEM1

PDB ID 1xpb

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