Biochemistry
Article
respectively, in SWV; Estep, staircase base potential in SWV;
ESW, square-wave pulse amplitude; EPR, electron paramagnetic
resonance; ET, electron transfer; f, square-wave frequency; FnY
(20) Chandler, D. (2005) Interfaces and the driving force of
hydrophobic assembly. Nature 437, 640−647.
(21) Westerlund, K., Berry, B. W., Privett, H. K., and Tommos, C.
(
2005) Exploring amino-acid radical chemistry: Protein engineering
and de novo design. Biochim. Biophys. Acta 1707, 103−116.
22) Martínez-Rivera, M. C., Berry, B. W., Valentine, K. G.,
(
n = 2 and 3), di- and trisubstituted fluorotyrosines,
respectively; F Y-RS, fluorotyrosine aminoacyl-tRNA synthe-
n
(
tase; pK , apparent pK ; I , I , and I , forward, reverse, and
app
a
for rev
net
Westerlund, K., Hay, S., and Tommos, C. (2011) Electrochemical
and structural properties of a protein system designed to generate
tyrosine Pourbaix diagrams. J. Am. Chem. Soc. 133, 17786−17795.
net currents, respectively, in SWV; PCET, proton-coupled
electron transfer; PGE, pyrolytic graphite edge; RNR,
ribonucleotide reductase; SWV, square-wave voltammetry;
(23) Berry, B. W., Martínez-Rivera, M. C., and Tommos, C. (2012)
•
TPL, tyrosine phenol lyase; Y , tyrosine radical.
Reversible voltammograms and a Pourbaix diagram for a protein
tyrosine radical. Proc. Natl. Acad. Sci. U.S.A. 109, 9739−9743.
(
24) Tommos, C., Valentine, K. G., Martínez-Rivera, M. C., Liang, L.,
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dx.doi.org/10.1021/bi401494f | Biochemistry 2013, 52, 8907−8915