Uno Ferro, a de novo Designed Protein, Binds Transition Metals with High Affinity and Stabilizes Semiquinone Radical Anion.

TitleUno Ferro, a de novo Designed Protein, Binds Transition Metals with High Affinity and Stabilizes Semiquinone Radical Anion.
Publication TypeJournal Article
Year of Publication2019
AuthorsYoon, J. H., A. V. Kulesha, Z. Lengyel-Zhand, A. N. Volkov, J. J. Rempillo, A. D'Souza, C. Costeas, C. Chester, E. R. Caselle, and O. V. Makhlynets
JournalChemistry
Volume25
Issue67
Pagination15252-15256
Date Published2019 Dec 02
ISSN1521-3765
Abstract

Metalloenzymes often utilize radicals in order to facilitate chemical reactions. Recently, DeGrado and co-workers have discovered that model proteins can efficiently stabilize semiquinone radical anion produced by oxidation of 3,5-di-tert-butylcatechol (DTBC) in the presence of two zinc ions. Here, we show that the number and the nature of metal ions have relatively minor effect on semiquinone stabilization in model proteins, with a single metal ion being sufficient for radical stabilization. The radical is stabilized by both metal ion, hydrophobic sequestration, and interactions with the hydrophilic residues in the protein interior resulting in a remarkable, nearly 500 mV change in the redox potential of the SQ /catechol couple compared to bulk aqueous solution. Moreover, we have created 4G-UFsc, a single metal ion-binding protein with pm affinity for zinc that is higher than any other reported model systems and is on par with many natural zinc-containing proteins. We expect that the robust and easy-to-modify DFsc/UFsc family of proteins will become a versatile tool for mechanistic model studies of metalloenzymes.

DOI10.1002/chem.201904020
Alternate JournalChemistry
PubMed ID31509280
PubMed Central IDPMC6891133
Grant ListP41 GM103521 / GM / NIGMS NIH HHS / United States
S10 OD012254 / OD / NIH HHS / United States
/ / Syracuse University /
subject_category: 
Research group: