2rdb: Difference between revisions
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< | ==X-ray Crystal Structure of Toluene/o-Xylene Monooxygenase Hydroxylase I100W Mutant== | ||
<StructureSection load='2rdb' size='340' side='right'caption='[[2rdb]], [[Resolution|resolution]] 2.10Å' scene=''> | |||
You may | == Structural highlights == | ||
or the | <table><tr><td colspan='2'>[[2rdb]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_stutzeri Pseudomonas stutzeri]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RDB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2RDB 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]] 2.1Å</td></tr> | |||
-- | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MPO:3[N-MORPHOLINO]PROPANE+SULFONIC+ACID'>MPO</scene>, <scene name='pdbligand=P6G:HEXAETHYLENE+GLYCOL'>P6G</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=2rdb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2rdb OCA], [https://pdbe.org/2rdb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2rdb RCSB], [https://www.ebi.ac.uk/pdbsum/2rdb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2rdb ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/O87798_STUST O87798_STUST] | |||
== 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/rd/2rdb_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=2rdb ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
At its carboxylate-bridged diiron active site, the hydroxylase component of toluene/o-xylene monooxygenase activates dioxygen for subsequent arene hydroxylation. In an I100W variant of this enzyme, we characterized the formation and decay of two species formed by addition of dioxygen to the reduced, diiron(II) state by rapid-freeze quench (RFQ) EPR, Mossbauer, and ENDOR spectroscopy. The dependence of the formation and decay rates of this mixed-valent transient on pH and the presence of phenol, propylene, or acetylene was investigated by double-mixing stopped-flow optical spectroscopy. Modification of the alpha-subunit of the hydroxylase after reaction of the reduced protein with dioxygen-saturated buffer was investigated by tryptic digestion coupled mass spectrometry. From these investigations, we conclude that (i) a diiron(III,IV)-W* transient, kinetically linked to a preceding diiron(III) intermediate, arises from the one-electron oxidation of W100, (ii) the tryptophan radical is deprotonated, (iii) rapid exchange of either a terminal water or hydroxide ion with water occurs at the ferric ion in the diiron(III,IV) cluster, and (iv) the diiron(III,IV) core and W* decay to the diiron(III) product by a common mechanism. No transient radical was observed by stopped-flow optical spectroscopy for reactions of the reduced hydroxylase variants I100Y, L208F, and F205W with dioxygen. The absence of such species, and the deprotonated state of the tryptophanyl radical in the diiron(III,IV)-W* transient, allow for a conservative estimate of the reduction potential of the diiron(III) intermediate as lying between 1.1 and 1.3 V. We also describe the X-ray crystal structure of the I100W variant of ToMOH. | |||
Dioxygen activation at non-heme diiron centers: oxidation of a proximal residue in the I100W variant of toluene/o-xylene monooxygenase hydroxylase.,Murray LJ, Garcia-Serres R, McCormick MS, Davydov R, Naik SG, Kim SH, Hoffman BM, Huynh BH, Lippard SJ Biochemistry. 2007 Dec 25;46(51):14795-809. Epub 2007 Nov 29. PMID:18044971<ref>PMID:18044971</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2rdb" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Monooxygenase 3D structures|Monooxygenase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | [[Category: Large Structures]] | ||
== | |||
< | |||
[[Category: Pseudomonas stutzeri]] | [[Category: Pseudomonas stutzeri]] | ||
[[Category: Davydov | [[Category: Davydov R]] | ||
[[Category: Garcia-Serres | [[Category: Garcia-Serres R]] | ||
[[Category: Hoffman | [[Category: Hoffman BM]] | ||
[[Category: Huynh | [[Category: Huynh BH]] | ||
[[Category: Lippard | [[Category: Lippard SJ]] | ||
[[Category: McCormick | [[Category: McCormick MS]] | ||
[[Category: Murray | [[Category: Murray LJ]] | ||
[[Category: Naik | [[Category: Naik S]] | ||
Latest revision as of 14:54, 30 August 2023
X-ray Crystal Structure of Toluene/o-Xylene Monooxygenase Hydroxylase I100W MutantX-ray Crystal Structure of Toluene/o-Xylene Monooxygenase Hydroxylase I100W Mutant
Structural highlights
FunctionEvolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAt its carboxylate-bridged diiron active site, the hydroxylase component of toluene/o-xylene monooxygenase activates dioxygen for subsequent arene hydroxylation. In an I100W variant of this enzyme, we characterized the formation and decay of two species formed by addition of dioxygen to the reduced, diiron(II) state by rapid-freeze quench (RFQ) EPR, Mossbauer, and ENDOR spectroscopy. The dependence of the formation and decay rates of this mixed-valent transient on pH and the presence of phenol, propylene, or acetylene was investigated by double-mixing stopped-flow optical spectroscopy. Modification of the alpha-subunit of the hydroxylase after reaction of the reduced protein with dioxygen-saturated buffer was investigated by tryptic digestion coupled mass spectrometry. From these investigations, we conclude that (i) a diiron(III,IV)-W* transient, kinetically linked to a preceding diiron(III) intermediate, arises from the one-electron oxidation of W100, (ii) the tryptophan radical is deprotonated, (iii) rapid exchange of either a terminal water or hydroxide ion with water occurs at the ferric ion in the diiron(III,IV) cluster, and (iv) the diiron(III,IV) core and W* decay to the diiron(III) product by a common mechanism. No transient radical was observed by stopped-flow optical spectroscopy for reactions of the reduced hydroxylase variants I100Y, L208F, and F205W with dioxygen. The absence of such species, and the deprotonated state of the tryptophanyl radical in the diiron(III,IV)-W* transient, allow for a conservative estimate of the reduction potential of the diiron(III) intermediate as lying between 1.1 and 1.3 V. We also describe the X-ray crystal structure of the I100W variant of ToMOH. Dioxygen activation at non-heme diiron centers: oxidation of a proximal residue in the I100W variant of toluene/o-xylene monooxygenase hydroxylase.,Murray LJ, Garcia-Serres R, McCormick MS, Davydov R, Naik SG, Kim SH, Hoffman BM, Huynh BH, Lippard SJ Biochemistry. 2007 Dec 25;46(51):14795-809. Epub 2007 Nov 29. PMID:18044971[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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