Sökning: id:"swepub:oai:DiVA.org:su-80014" >
Reversible voltammo...
Reversible voltammograms and a Pourbaix diagram for a protein tyrosine radical
-
- Berry, Bruce W., 1974- (författare)
- Stockholms universitet,Institutionen för biokemi och biofysik,University of Pennsylvania, USA
-
Martinez-Rivera, Melissa C. (författare)
-
- Tommos, Cecilia (författare)
- Stockholms universitet,Institutionen för biokemi och biofysik,University of Pennsylvania, USA
-
(creator_code:org_t)
- 2012-06-06
- 2012
- Engelska.
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 109:25, s. 9739-9743
- Relaterad länk:
-
https://www.pnas.org...
-
visa fler...
-
https://urn.kb.se/re...
-
https://doi.org/10.1...
-
visa färre...
Abstract
Ämnesord
Stäng
- Reversible voltammograms and a voltammetry half-wave potential versus solution pH diagram are described for a protein tyrosine radical. This work required a de novo designed tyrosine-radical protein displaying a unique combination of structural and electrochemical properties. The alpha Y-3 protein is structurally stable across a broad pH range. The redox-active tyrosine Y32 resides in a desolvated and well-structured environment. Y32 gives rise to reversible square-wave and differential pulse voltammograms at alkaline pH. The formal potential of the Y32-O-center dot/Y32-OH redox couple is determined to 918 +/- 2 mV versus the normal hydrogen electrode at pH 8.40 +/- 0.01. The observation that Y32 gives rise to fully reversible voltammograms translates into an estimated lifetime of >= 30 ms for the Y32-O-center dot state. This illustrates the range of tyrosine-radical stabilization that a structured protein can offer. Y32 gives rise to quasireversible square-wave and differential pulse voltammograms at acidic pH. These voltammograms represent the Y32 species at the upper edge of the quasirevesible range. The square-wave net potential closely approximates the formal potential of the Y32-O center dot/Y32-OH redox couple to 1,070 +/- 1 mV versus the normal hydrogen electrode at pH 5.52 +/- 0.01. The differential pulse voltammetry half-wave potential of the Y32-O-center dot/Y32-OH redox pair is measured between pH 4.7 and 9.0. These results are described and analyzed.
Ämnesord
- NATURVETENSKAP -- Biologi (hsv//swe)
- NATURAL SCIENCES -- Biological Sciences (hsv//eng)
Nyckelord
- protein voltammetry
- proton-coupled electron transfer
- Biochemistry
- biokemi
Publikations- och innehållstyp
- ref (ämneskategori)
- art (ämneskategori)
Hitta via bibliotek
Till lärosätets databas