Key Intermediate Species Reveal the Copper(II)-Exchange Pathway in Biorelevant ATCUN/NTS Complexes

Key Intermediate Species Reveal the Copper(II)-Exchange Pathway in Biorelevant ATCUN/NTS Complexes

Kotuniak, Radosław (Polish Academy of Sciences)
Strampraad, M.J.F. (TU Delft BT/Biocatalysis)
Bossak-Ahmad, Karolina (Polish Academy of Sciences)
Wawrzyniak, Urszula E. (Warsaw University of Technology)
Ufnalska, Iwona (Warsaw University of Technology)
Hagedoorn, P.L. (TU Delft BT/Biocatalysis)
Bal, Wojciech (Polish Academy of Sciences)

2020

The amino-terminal copper and nickel/N-terminal site (ATCUN/NTS) present in proteins and bioactive peptides exhibits high affinity towards Cu^II ions and have been implicated in human copper physiology. Little is known, however, about the rate and exact mechanism of formation of such complexes. We used the stopped-flow and microsecond freeze-hyperquenching (MHQ) techniques supported by steady-state spectroscopic and electrochemical data to demonstrate the formation of partially coordinated intermediate Cu^II complexes formed by glycyl–glycyl–histidine (GGH) peptide, the simplest ATCUN/NTS model. One of these novel intermediates, characterized by two-nitrogen coordination, t_1/2≈100 ms at pH 6.0 and the ability to maintain the Cu^II/Cu^I redox pair is the best candidate for the long-sought reactive species in extracellular copper transport.

amino-terminal copper and nickel (ATCUN) motif
copper
electrochemistry
EPR spectroscopy
peptides

http://resolver.tudelft.nl/uuid:49354286-6e77-437c-8789-33fbf265de02

https://doi.org/10.1002/anie.202004264

1433-7851

Angewandte Chemie (International Edition), 59 (28), 11234-11239

Institutional Repository

journal article

© 2020 Radosław Kotuniak, M.J.F. Strampraad, Karolina Bossak-Ahmad, Urszula E. Wawrzyniak, Iwona Ufnalska, P.L. Hagedoorn, Wojciech Bal