Intramolecular Excited State Electronic Coupling Along an alpha-Helical Peptide.
Several families of peptides composed of alternating L-alanine (Ala) and alpha-aminoisobutyric acid (Aib) residues with an appended N,N-dimethylanilino and/or 2-naphthalenyl group exist in MeOH and CDCl(3) as alpha-helices. Steady state and time-resolved fluorescence measurements show that the distance and dihedral angle between the appended donor and acceptor and the alignment of the vectors for intramolecular charge transfer interaction (from donor to acceptor) with or against that of the helical dipole moment significantly influence the efficiency of photoinduced electronic coupling and, hence, of intramolecular fluorescence quenching.
Batchelder
Traci L.
TL
Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712.
Fox
Robert J.
RJ
Meier
Mark S.
MS
Fox
Marye Anne
MA