2bjs: Difference between revisions
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== | ==Isopenicillin N synthase C-terminal truncation mutant== | ||
<StructureSection load='2bjs' size='340' side='right'caption='[[2bjs]], [[Resolution|resolution]] 1.30Å' scene=''> | |||
[ | == Structural highlights == | ||
[ | <table><tr><td colspan='2'>[[2bjs]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Aspergillus_nidulans Aspergillus nidulans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BJS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2BJS 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]] 1.3Å</td></tr> | ||
[ | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACV:L-D-(A-AMINOADIPOYL)-L-CYSTEINYL-D-VALINE'>ACV</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=MEE:METHANETHIOL'>MEE</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=2bjs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bjs OCA], [https://pdbe.org/2bjs PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2bjs RCSB], [https://www.ebi.ac.uk/pdbsum/2bjs PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2bjs ProSAT]</span></td></tr> | ||
</table> | |||
== Function == | |||
[ | [https://www.uniprot.org/uniprot/IPNA_EMENI IPNA_EMENI] Isopenicillin N synthase; part of the gene cluster that mediates the biosynthesis of penicillin, the world's most important antibiotic (PubMed:3319778, PubMed:11755401). IpnA catalyzes the cyclization of the tripeptide N-[(5S)-5-amino-5-carboxypentanoyl]-L-cysteinyl-D-valine (LLD-ACV or ACV) to form isopenicillin N (IPN) that contains the beta-lactam nucleus (PubMed:3319778, PubMed:11755401, PubMed:28703303). The penicillin biosynthesis occurs via 3 enzymatic steps, the first corresponding to the production of the tripeptide N-[(5S)-5-amino-5-carboxypentanoyl]-L-cysteinyl-D-valine (LLD-ACV or ACV) by the NRPS acvA. The tripeptide ACV is then cyclized to isopenicillin N (IPN) by the isopenicillin N synthase ipnA that forms the beta-lactam nucleus. Finally, the alpha-aminoadipyl side chain is exchanged for phenylacetic acid by the isopenicillin N acyltransferase penDE to yield penicillin in the peroxisomal matrix (By similarity).[UniProtKB:P08703]<ref>PMID:11755401</ref> <ref>PMID:28703303</ref> <ref>PMID:3319778</ref> | ||
[[ | == 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/bj/2bjs_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=2bjs ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Isopenicillin N synthase (IPNS) catalyses the four-electron oxidation of a tripeptide, l-delta-(alpha-aminoadipoyl)-l-cysteinyl-d-valine (ACV), to give isopenicillin N (IPN), the first-formed beta-lactam in penicillin and cephalosporin biosynthesis. IPNS catalysis is dependent upon an iron(II) cofactor and oxygen as a co-substrate. In the absence of substrate, the carbonyl oxygen of the side-chain amide of the penultimate residue, Gln330, co-ordinates to the active-site metal iron. Substrate binding ablates the interaction between Gln330 and the metal, triggering rearrangement of seven C-terminal residues, which move to take up a conformation that extends the final alpha-helix and encloses ACV in the active site. Mutagenesis studies are reported, which probe the role of the C-terminal and other aspects of the substrate binding pocket in IPNS. The hydrophobic nature of amino acid side-chains around the ACV binding pocket is important in catalysis. Deletion of seven C-terminal residues exposes the active site and leads to formation of a new type of thiol oxidation product. The isolated product is shown by LC-MS and NMR analyses to be the ene-thiol tautomer of a dithioester, made up from two molecules of ACV linked between the thiol sulfur of one tripeptide and the oxidised cysteinyl beta-carbon of the other. A mechanism for its formation is proposed, supported by an X-ray crystal structure, which shows the substrate ACV bound at the active site, its cysteinyl beta-carbon exposed to attack by a second molecule of substrate, adjacent. Formation of this product constitutes a new mode of reaction for IPNS and non-heme iron oxidases in general. | |||
Terminally Truncated Isopenicillin N Synthase Generates a Dithioester Product: Evidence for a Thioaldehyde Intermediate during Catalysis and a New Mode of Reaction for Non-Heme Iron Oxidases.,McNeill LA, Brown TJN, Sami M, Clifton IJ, Burzlaff NI, Claridge TDW, Adlington RM, Baldwin JE, Rutledge PJ, Schofield CJ Chemistry. 2017 Sep 18;23(52):12815-12824. doi: 10.1002/chem.201701592. Epub 2017, Aug 21. PMID:28703303<ref>PMID:28703303</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2bjs" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Isopenicillin N synthase|Isopenicillin N synthase]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Aspergillus nidulans]] | |||
[[Category: Large Structures]] | |||
[[Category: Burzlaff NI]] | |||
[[Category: Clifton IJ]] | |||
[[Category: McNeill LA]] | |||
[[Category: Sami M]] | |||