1yfd
From Proteopedia
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|PDB= 1yfd |SIZE=350|CAPTION= <scene name='initialview01'>1yfd</scene>, resolution 1.90Å | |PDB= 1yfd |SIZE=350|CAPTION= <scene name='initialview01'>1yfd</scene>, resolution 1.90Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=F2O:MU-OXO-DIIRON(III)'>F2O</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Ribonucleoside-diphosphate_reductase Ribonucleoside-diphosphate reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.17.4.1 1.17.4.1] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Ribonucleoside-diphosphate_reductase Ribonucleoside-diphosphate reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.17.4.1 1.17.4.1] </span> |
|GENE= nrdB, ftsB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | |GENE= nrdB, ftsB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1biq|1BIQ]], [[1pfr|1PFR]], [[1xik|1XIK]], [[1mxr|1MXR]], [[1pim|1PIM]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1yfd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yfd OCA], [http://www.ebi.ac.uk/pdbsum/1yfd PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1yfd RCSB]</span> | ||
}} | }} | ||
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[[Category: Poetsch, S.]] | [[Category: Poetsch, S.]] | ||
[[Category: Sjoeberg, B M.]] | [[Category: Sjoeberg, B M.]] | ||
| - | [[Category: F2O]] | ||
| - | [[Category: HG]] | ||
[[Category: di-iron center]] | [[Category: di-iron center]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:05:37 2008'' |
Revision as of 22:05, 30 March 2008
| |||||||
| , resolution 1.90Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | nrdB, ftsB (Escherichia coli) | ||||||
| Activity: | Ribonucleoside-diphosphate reductase, with EC number 1.17.4.1 | ||||||
| Related: | 1BIQ, 1PFR, 1XIK, 1MXR, 1PIM
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of the Y122H mutant of ribonucleotide reductase R2 protein from E. coli
Overview
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.
About this Structure
1YFD is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
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
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