Article

Evidence against the hopping mechanism as an important electron transfer pathway for conformationally constrained oligopeptides.

Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy.
Journal of the American Chemical Society (Impact Factor: 10.68). 02/2005; 127(2):492-3. DOI: 10.1021/ja043607e
Source: PubMed

ABSTRACT The rate constant of intramolecular electron transfer through oligopeptides based on the alpha-aminoisobutyric acid residue was determined as a function of the peptide length and found to depend weakly on the donor-acceptor separation. By measuring the electron-transfer activation energy and estimating the energy gap between donor and bridge, we were able to discard the electron hopping mechanism.

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