Electric field strength of the peptide helix macrodipole as measured by intramolecular stark spectroscopy

CHED 338

Eric Falcone, mkubasik@mail.fairfield.edu and Matthew Kubasik, mkubasik@mail.fairfield.edu. Department of Chemistry, Fairfield University, 1073 N. Benson Rd, Fairfield, CT 06824
The characterization of electric fields arising from the correlation of amide bond electric dipoles in protein and peptide helical secondary structures is of interest to both theoretical and experimental biomolecular scientists. We have performed measurements of this field by using a model helical peptide system containing an N-terminal chromophore that is responsive to electric fields. In contrast to previous studies of this type (e.g., Lockhart and Kim, Science, 257, 947 (1992)), our chromophore/peptide system is soluble in organic solvents. This allows us to take measurements in solvents of significantly lower dielectric strength than that of water. Results of our system in a series of solvents of widely varying dielectric strength will be presented. The results of our current study will be compared to previous results in our laboratory examining the influence of a helical peptide's electric field upon 19F NMR chemical shifts (ChemBioChem, 7, 1056 (2006)).

 

Undergraduate Research Poster Session
2:30 PM-4:30 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Chemical Education

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007