J. Phys. Chem. B 1997, 101, 8607-8616
8607
Peptide Conformational Dynamics and Vibrational Stark Effects Following Photoinitiated Disulfide Cleavage Martin Volk,†,‡ Yuriy Kholodenko,† Helen S. M. Lu,§ Edward A. Gooding,† William F. DeGrado,§ and Robin M. Hochstrasser*,† Department of Chemistry and Department of Biochemistry and Biophysics, The Johnson Foundation for Research in Biophysics, The UniVersity of PennsylVania, Philadelphia, PennsylVania 19104 ReceiVed: June 13, 1997; In Final Form: August 19, 1997X
Photoinitiation of relaxation of two peptides (labeled 1 and 2) and spectroscopic studies of the ensuing dynamics have led to new information about peptide conformational dynamics. Following photolysis of the aryl disulfide chromophore that constrains a peptide to be distorted from its equilibrium form, the S-S bond is broken in
