Collect. Czech. Chem. Commun. 2005, 70, 403-409

Raman Optical Activity of the Central Part of Hinge Peptide

Josef Kapitána, Vladimír Baumruka, Vladimír Gutb, Jan Hlaváčekb, Helena Dlouháb, Marie Urbanovác, Erich Wünschb and Petr Maloňb,*

a Institute of Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2, Czech Republic
b Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
c Department of Physics and Measurements, Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic


Central cyclic part of the hinge peptide (a parallel dimer of the pentapeptide Boc-Cys-Pro-Pro-Cys-Pro-NHCH3 with two disulfide bonds) derived from the sequence of human IgG1 is a rather rigid structure having predominantly polyproline II helical conformation as shown by vibrational circular dichroism spectra. It exhibits significant Raman optical activity (ROA) signal due to vibrations associated with the disulfide bridges. We report positive ROA for the S-S stretching vibration at 510 cm-1 and for the C-S stretching vibration at 655 cm-1. These signals can provide means to assess the conformation of disulfide bridges in proteins, otherwise difficult to investigate.

Keywords: Peptides; Conformation analysis; Chirality; Raman optical activity; Raman spectroscopy; Disulfide bridges; Vibrational circular dichroism; IgG1.

References: 22 live references.