View source for 4xe3


==OleP, the cytochrome P450 epoxidase from Streptomyces antibioticus involved in Oleandomycin biosynthesis: functional analysis and crystallographic structure in complex with clotrimazole.==
<StructureSection load='4xe3' size='340' side='right'caption='[[4xe3]], [[Resolution|resolution]] 2.65&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4xe3]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_antibioticus Streptomyces antibioticus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4XE3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4XE3 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]] 2.65&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL6:1-[(2-CHLOROPHENYL)(DIPHENYL)METHYL]-1H-IMIDAZOLE'>CL6</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</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=4xe3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4xe3 OCA], [https://pdbe.org/4xe3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4xe3 RCSB], [https://www.ebi.ac.uk/pdbsum/4xe3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4xe3 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q59819_STRAT Q59819_STRAT] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
BACKGROUND: OleP is a cyt P450 from Streptomyces antibioticus carrying out epoxigenation of the antibiotic oleandomycin during its biosynthesis. The timing of its reaction has not been fully clarified, doubts remain regarding its substrate and catalytic mechanism. METHODS: The crystal structure of OleP in complex with clotrimazole, an inhibitor of P450s used in therapy, was solved and the complex formation dynamics was characterized by equilibrium and kinetic binding studies and compared to ketoconazole, another azole differing for the N1-substituent. RESULTS: Clotrimazole coordinates the heme and occupies the active site. Most of the residues interacting with clotrimazole are conserved and involved in substrate binding in MycG, the P450 epoxigenase with the highest homology with OleP. Kinetic characterization of inhibitor binding revealed OleP to follow a simple bimolecular reaction, without detectable intermediates. CONCLUSIONS: Clotrimazole-bound OleP adopts an open form, held by a pi-pi stacking chain that fastens helices F and G and the FG loop. Affinity is affected by the interactions of the N1 substituent within the active site, given the one order of magnitude difference of the off-rate constants between clotrimazole and ketoconazole. Based on structural similarities with MycG, we propose a binding mode for both oleandomycin intermediates, that are the candidate substrates of OleP. GENERAL SIGNIFICANCE: Among P450 epoxigenases OleP is the only one that introduces an epoxide on a non-activated C-C bond. The data here presented are necessary to understand the rare chemistry carried out by OleP, to engineer it and to design more selective and potent P450-targeted drugs.

Functional analysis and crystallographic structure of clotrimazole bound OleP, a cytochrome P450 epoxidase from Streptomyces antibioticus involved in oleandomycin biosynthesis.,Montemiglio LC, Parisi G, Scaglione A, Sciara G, Savino C, Vallone B Biochim Biophys Acta. 2016 Mar;1860(3):465-75. doi: 10.1016/j.bbagen.2015.10.009., Epub 2015 Oct 22. PMID:26475642<ref>PMID:26475642</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4xe3" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces antibioticus]]
[[Category: Montemiglio LC]]
[[Category: Parisi G]]
[[Category: Savino C]]
[[Category: Scaglione A]]
[[Category: Vallone B]]