View source for 1b12


==CRYSTAL STRUCTURE OF TYPE 1 SIGNAL PEPTIDASE FROM ESCHERICHIA COLI IN COMPLEX WITH A BETA-LACTAM INHIBITOR==
<StructureSection load='1b12' size='340' side='right'caption='[[1b12]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1b12]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_BL21(DE3) Escherichia coli BL21(DE3)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B12 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1B12 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]] 1.95&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1PN:PROP-2-EN-1-YL+(2S)-2-[(2S,3R)-3-(ACETYLOXY)-1-OXOBUTAN-2-YL]-2,3-DIHYDRO-1,3-THIAZOLE-4-CARBOXYLATE'>1PN</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=1b12 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b12 OCA], [https://pdbe.org/1b12 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1b12 RCSB], [https://www.ebi.ac.uk/pdbsum/1b12 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1b12 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/LEP_ECOLI LEP_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/b1/1b12_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=1b12 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The signal peptidase (SPase) from Escherichia coli is a membrane-bound endopeptidase with two amino-terminal transmembrane segments and a carboxy-terminal catalytic region which resides in the periplasmic space. SPase functions to release proteins that have been translocated into the inner membrane from the cell interior, by cleaving off their signal peptides. We report here the X-ray crystal structure of a catalytically active soluble fragment of E. coli SPase (SPase delta2-75). We have determined this structure at 1.9 A resolution in a complex with an inhibitor, a beta-lactam (5S,6S penem), which is covalently bound as an acyl-enzyme intermediate to the gamma-oxygen of a serine residue at position 90, demonstrating that this residue acts as the nucleophile in the hydrolytic mechanism of signal-peptide cleavage. The structure is consistent with the use by SPase of Lys 145 as a general base in the activation of the nucleophilic Ser90, explains the specificity requirement at the signal-peptide cleavage site, and reveals a large exposed hydrophobic surface which could be a site for an intimate association with the membrane. As enzymes that are essential for cell viability, bacterial SPases present a feasible antibacterial target: our determination of the SPase structure therefore provides a template for the rational design of antibiotic compounds.

Crystal structure of a bacterial signal peptidase in complex with a beta-lactam inhibitor.,Paetzel M, Dalbey RE, Strynadka NC Nature. 1998 Nov 12;396(6707):186-90. PMID:9823901<ref>PMID:9823901</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1b12" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Dalbey R]]
[[Category: Paetzel M]]
[[Category: Strynadka NCJ]]