Vibrational studies of the disulfied group in proteins part IV. SS and CS stretch frequencies of known peptide and protein disulfide bridges

Abstract

We have used our previously derived ab initio disulfide and empirical polypeptide force field to calculate SS and CS stretch frequencies of disulfide bridges in a cyclic octapeptide and six proteins of known structure. Comparisons with Raman spectra show that the observed bands are very well reproduced by the normal mode calculations, thus validating the use of these force fields in studying detailed correlations between such spectra and disulfide bridge geometry.