Conformational effects on the electron-transfer efficiency in peptide foldamers based on alpha,alpha-disubstituted
Emanuela Gatto1, Alessandro Porchetta, Lorenzo Stella
1Department of Chemical Sciences and Technologies, University of Rome 'Tor Vergata', I-00133 Rome.
Abstract:
Peptide foldamers based on alpha,alpha-disubstituted glycyl residues were synthesized and chemically characterized to investigate the effects of the electric field generated by a 3(10)-helix on the rate of intramolecular photoinduced electron-transfer reactions. To this end, two new octapeptides having identical sequences were suitably side-chain functionalized with the same electron-transfer donor-acceptor pair, but inverting the position of the pair along the main chain. The electron-transfer rate constants, measured by time-resolved spectroscopy techniques (nanosecond transient absorption and time-resolved fluorescence), indicated that, in the case of the 3(10)-helix, the electrostatic effect is significant, but smaller than that obtained for alpha-helical peptides. This finding can be likely ascribed to the distortion of the H-bond network with respect to the helical axis taking place in the former secondary structure. Overall, these results could have implications on electron-transfer phenomena in model and biomembranes facilitated by peptaibiotics.
More Related Videos
Related Concept Videos
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Folding
Protein Organization
Protein Organization
The primary structure of a protein is its amino acid sequence.
Protein and Protein Structure
A protein's shape is critical to its function. For example, an enzyme can...
Protein Folding Quality Check in the RER


