1yfd: Difference between revisions
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< | ==Crystal structure of the Y122H mutant of ribonucleotide reductase R2 protein from E. coli== | ||
<StructureSection load='1yfd' size='340' side='right'caption='[[1yfd]], [[Resolution|resolution]] 1.90Å' scene=''> | |||
You may | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1yfd]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YFD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1YFD 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]] 1.9Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FEO:MU-OXO-DIIRON'>FEO</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</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=1yfd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yfd OCA], [https://pdbe.org/1yfd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1yfd RCSB], [https://www.ebi.ac.uk/pdbsum/1yfd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1yfd ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/RIR2_ECOLI RIR2_ECOLI] Provides the precursors necessary for DNA synthesis. Catalyzes the biosynthesis of deoxyribonucleotides from the corresponding ribonucleotides. R2 contains the tyrosyl radical required for catalysis. | |||
== 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/yf/1yfd_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=1yfd ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The R2 protein subunit of class I ribonucleotide reductase (RNR) belongs to a structurally related family of oxygen bridged diiron proteins. In wild-type R2 of Escherichia coli, reductive cleavage of molecular oxygen by the diferrous iron center generates a radical on a nearby tyrosine residue (Tyr122), which is essential for the enzymatic activity of RNR, converting ribonucleotides into deoxyribonucleotides. In this work, we characterize the mutant E. coli protein R2-Y122H, where the radical site is substituted with a histidine residue. The x-ray structure verifies the mutation. R2-Y122H contains a novel stable paramagnetic center which we name H, and which we have previously proposed to be a diferric iron center with a strongly coupled radical, Fe(III)Fe(III)R.. Here we report a detailed characterization of center H, using 1H/2H -14N/15N- and 57Fe-ENDOR in comparison with the Fe(III)Fe(IV) intermediate X observed in the iron reconstitution reaction of R2. Specific deuterium labeling of phenylalanine residues reveals that the radical results from a phenylalanine. As Phe208 is the only phenylalanine in the ligand sphere of the iron site, and generation of a phenyl radical requires a very high oxidation potential, we propose that in Y122H residue Phe208 is hydroxylated, as observed earlier in another mutant (R2-Y122F/E238A), and further oxidized to a phenoxyl radical, which is coordinated to Fe1. This work demonstrates that small structural changes can redirect the reactivity of the diiron site, leading to oxygenation of a hydrocarbon, as observed in the structurally similar methane monoxygenase, and beyond, to formation of a stable iron-coordinated radical. | |||
A new tyrosyl radical on Phe208 as ligand to the diiron center in Escherichia coli ribonucleotide reductase, mutant R2-Y122H. Combined x-ray diffraction and EPR/ENDOR studies.,Kolberg M, Logan DT, Bleifuss G, Potsch S, Sjoberg BM, Graslund A, Lubitz W, Lassmann G, Lendzian F J Biol Chem. 2005 Mar 25;280(12):11233-46. Epub 2005 Jan 5. PMID:15634667<ref>PMID:15634667</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1yfd" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Ribonucleotide reductase 3D structures|Ribonucleotide reductase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | |||
== | |||
< | |||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Bleifuss | [[Category: Bleifuss G]] | ||
[[Category: Graeslund | [[Category: Graeslund A]] | ||
[[Category: Kolberg | [[Category: Kolberg M]] | ||
[[Category: Lassmann | [[Category: Lassmann G]] | ||
[[Category: Lendzian | [[Category: Lendzian F]] | ||
[[Category: Logan | [[Category: Logan DT]] | ||
[[Category: Lubitz | [[Category: Lubitz W]] | ||
[[Category: Poetsch | [[Category: Poetsch S]] | ||
[[Category: Sjoeberg | [[Category: Sjoeberg BM]] | ||