2bjs: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
== | |||
==Isopenicillin N synthase C-terminal truncation mutant== | |||
<StructureSection load='2bjs' size='340' side='right' caption='[[2bjs]], [[Resolution|resolution]] 1.30Å' scene=''> | <StructureSection load='2bjs' size='340' side='right' caption='[[2bjs]], [[Resolution|resolution]] 1.30Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
Line 6: | Line 7: | ||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1bk0|1bk0]], [[1blz|1blz]], [[1hb1|1hb1]], [[1hb2|1hb2]], [[1hb3|1hb3]], [[1hb4|1hb4]], [[1ips|1ips]], [[1obn|1obn]], [[1oc1|1oc1]], [[1odm|1odm]], [[1odn|1odn]], [[1qiq|1qiq]], [[1qje|1qje]], [[1qjf|1qjf]], [[1uzw|1uzw]], [[1w03|1w03]], [[1w04|1w04]], [[1w05|1w05]], [[1w06|1w06]], [[1w3v|1w3v]], [[1w3x|1w3x]], [[2bu9|2bu9]]</td></tr> | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1bk0|1bk0]], [[1blz|1blz]], [[1hb1|1hb1]], [[1hb2|1hb2]], [[1hb3|1hb3]], [[1hb4|1hb4]], [[1ips|1ips]], [[1obn|1obn]], [[1oc1|1oc1]], [[1odm|1odm]], [[1odn|1odn]], [[1qiq|1qiq]], [[1qje|1qje]], [[1qjf|1qjf]], [[1uzw|1uzw]], [[1w03|1w03]], [[1w04|1w04]], [[1w05|1w05]], [[1w06|1w06]], [[1w3v|1w3v]], [[1w3x|1w3x]], [[2bu9|2bu9]]</td></tr> | ||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Isopenicillin-N_synthase Isopenicillin-N synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.21.3.1 1.21.3.1] </span></td></tr> | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Isopenicillin-N_synthase Isopenicillin-N synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.21.3.1 1.21.3.1] </span></td></tr> | ||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2bjs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bjs OCA], [http://pdbe.org/2bjs PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2bjs RCSB], [http://www.ebi.ac.uk/pdbsum/2bjs PDBsum]</span></td></tr> | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2bjs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bjs OCA], [http://pdbe.org/2bjs PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2bjs RCSB], [http://www.ebi.ac.uk/pdbsum/2bjs PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2bjs ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
Line 14: | Line 15: | ||
Check<jmol> | Check<jmol> | ||
<jmolCheckbox> | <jmolCheckbox> | ||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bj/2bjs_consurf.spt"</scriptWhenChecked> | <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> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> | ||
</jmolCheckbox> | </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/ | </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="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== | ==See Also== | ||
*[[Isopenicillin N synthase|Isopenicillin N synthase]] | *[[Isopenicillin N synthase|Isopenicillin N synthase]] | ||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> |
Revision as of 10:29, 6 December 2017
Isopenicillin N synthase C-terminal truncation mutantIsopenicillin N synthase C-terminal truncation mutant
Structural highlights
Function[IPNS_EMENI] Removes, in the presence of oxygen, 4 hydrogen atoms from delta-L-(alpha-aminoadipyl)-L-cysteinyl-D-valine (ACV) to form the azetidinone and thiazolidine rings of isopenicillin. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIsopenicillin 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|