+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

2,3-difluorotyrosine at position 356 of ribonucleotide reductase R2: a probe of long-range proton-coupled electron transfer



2,3-difluorotyrosine at position 356 of ribonucleotide reductase R2: a probe of long-range proton-coupled electron transfer



Journal of the American Chemical Society 125(35): 10506-7



Escherichia coli class I ribonucleotide reductase catalyzes the conversion of ribonucleotides to deoxyribonucleotides and consists of two subunits: R1 and R2. R1 possesses the active site, while R2 harbors the essential diferric-tyrosyl radical (Y*) cofactor. The Y* on R2 is proposed to generate a transient thiyl radical on R1, 35 A distant, through amino acid radical intermediates. To study the putative long-range proton-coupled electron transfer (PCET), R2 (375 residues) was prepared semisynthetically using intein technology. Y356, a putative intermediate in the pathway, was replaced with 2,3-difluorotyrosine (F2Y, pKa = 7.8). pH rate profiles (pH 6.5-9.0) of wild-type and F2Y-R2 were very similar. Thus, a proton can be lost from the putative PCET pathway without affecting nucleotide reduction. The current model involving H* transfer is thus unlikely.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 034269487

Download citation: RISBibTeXText

PMID: 12940718

DOI: 10.1021/ja036242r


Related references

Long-range proton-coupled electron transfer in the iEscherichia coli class Ia ribonucleotide reductase. Essays in Biochemistry 61(2): 281-292, 2017

Radical initiation in the class I ribonucleotide reductase: long-range proton-coupled electron transfer?. Chemical Reviews 103(6): 2167-2201, 2003

Ribonucleotide reductase Unnatural amino acids to probe proton coupled electron transfer. Abstracts of Papers American Chemical Society 226(1-2): BIOL 54, 2003

Radical initiation by the class I ribonucleotide reductases Long range proton coupled electron transfer?. Abstracts of Papers American Chemical Society 225(1-2): ORGN 228, 2003

Ribonucleotide Reductase Coupled Electron/Proton Transfer Mechanisms. Biochemical Society Transactions 27(1): A30.3-A30, 1999

Transient radicals and coupled electron/proton transfer in ribonucleotide reductase. Journal of Inorganic Biochemistry 74(1-4): 51, April 30, 1999

Use of 2,3,5-F(3)Y-β2 and 3-NH(2)Y-α2 to study proton-coupled electron transfer in Escherichia coli ribonucleotide reductase. Biochemistry 50(8): 1403-1411, 2011

Solvent and Temperature Probes of the Long-Range Electron-Transfer Step in Tyramine β-Monooxygenase: Demonstration of a Long-Range Proton-Coupled Electron-Transfer Mechanism. Journal of the American Chemical Society 137(17): 5720-5729, 2016

Redox-linked conformational control of proton-coupled electron transfer: Y122 in the ribonucleotide reductase β2 subunit. Journal of Physical Chemistry. B 117(28): 8457-8468, 2014

Function of the diiron cluster of Escherichia coli class Ia ribonucleotide reductase in proton-coupled electron transfer. Journal of the American Chemical Society 135(23): 8585-8593, 2014

Proton Coupled Electron Transfer and Redox Active Tyrosines: Structure and Function of the Tyrosyl Radicals in Ribonucleotide Reductase and Photosystem II. Journal of Physical Chemistry Letters 3(4): 543-554, 2012

Hydrogen bond network between amino acid radical intermediates on the proton-coupled electron transfer pathway of E. coli α2 ribonucleotide reductase. Journal of the American Chemical Society 137(1): 289-298, 2016

Evidence by site-directed mutagenesis supports long-range electron transfer in mouse ribonucleotide reductase. Biochemistry. 34(13): 4267-4275, 1995

Long-range proton-coupled electron transfer in phenol-Ru(2,2'-bipyrazine)3(2+) dyads. Physical Chemistry Chemical Physics 16(8): 3617-3622, 2014

Tyrosine oxidation in heme oxygenase: examination of long-range proton-coupled electron transfer. Journal of Biological Inorganic Chemistry 19(7): 1137-1148, 2015