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CuA-based chimeric T1 copper sites allow for independent modulation of reorganization energy and reduction potential.

ABSTRACT: Attaining rational modulation of thermodynamic and kinetic redox parameters of metalloproteins is a key milestone towards the (re)design of proteins with new or improved redox functions. Here we report that implantation of ligand loops from natural T1 proteins into the scaffold of a CuA protein leads to a series of distorted T1-like sites that allow for independent modulation of reduction potentials (E°') and electron transfer reorganization energies (?). On the one hand E°' values could be fine-tuned over 120 mV without affecting ?. On the other, ? values could be modulated by more than a factor of two while affecting E°' only by a few millivolts. These results are in sharp contrast to previous studies that used T1 cupredoxin folds, thus highlighting the importance of the protein scaffold in determining such parameters.

SUBMITTER: Szuster J

PROVIDER: S-EPMC7480511 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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CuA-based chimeric T1 copper sites allow for independent modulation of reorganization energy and reduction potential.

Szuster Jonathan J Zitare Ulises A UA Castro María A MA Leguto Alcides J AJ Morgada Marcos N MN Vila Alejandro J AJ Murgida Daniel H DH

Chemical science 20200601 24

Attaining rational modulation of thermodynamic and kinetic redox parameters of metalloproteins is a key milestone towards the (re)design of proteins with new or improved redox functions. Here we report that implantation of ligand loops from natural T1 proteins into the scaffold of a CuA protein leads to a series of distorted T1-like sites that allow for independent modulation of reduction potentials (E°') and electron transfer reorganization energies (λ). On the one hand ...[more]

PMID: 32953013

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