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Photoinduced Electron Transfer Elicits a Change in the Static Dielectric Constant of a de Novo Designed Protein.

ABSTRACT: We provide a direct measure of the change in effective dielectric constant (?(S)) within a protein matrix after a photoinduced electron transfer (ET) reaction. A linked donor-bridge-acceptor molecule, PZn-Ph-NDI, consisting of a (porphinato)Zn donor (PZn), a phenyl bridge (Ph), and a naphthalene diimide acceptor (NDI), is shown to be a "meter" to indicate protein dielectric environment. We calibrated PZn-Ph-NDI ET dynamics as a function of solvent dielectric, and computationally de novo designed a protein SCPZnI3 to bind PZn-Ph-NDI in its interior. Mapping the protein ET dynamics onto the calibrated ET catalogue shows that SCPZnI3 undergoes a switch in the effective dielectric constant following photoinduced ET, from ?(S) ? 8 to ?(S) ? 3.

SUBMITTER: Polizzi NF

PROVIDER: S-EPMC5049705 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Photoinduced Electron Transfer Elicits a Change in the Static Dielectric Constant of a de Novo Designed Protein.

Polizzi Nicholas F NF Eibling Matthew J MJ Perez-Aguilar Jose Manuel JM Rawson Jeff J Lanci Christopher J CJ Fry H Christopher HC Beratan David N DN Saven Jeffery G JG Therien Michael J MJ

Journal of the American Chemical Society 20160211 7

We provide a direct measure of the change in effective dielectric constant (ε(S)) within a protein matrix after a photoinduced electron transfer (ET) reaction. A linked donor-bridge-acceptor molecule, PZn-Ph-NDI, consisting of a (porphinato)Zn donor (PZn), a phenyl bridge (Ph), and a naphthalene diimide acceptor (NDI), is shown to be a "meter" to indicate protein dielectric environment. We calibrated PZn-Ph-NDI ET dynamics as a function of solvent dielectric, and computationally de novo designed ...[more]

PMID: 26840013

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