The Raman detection of peptide tyrosine phosphorylation

• Published in: Analytical biochemistry 2004-09, Vol.332 (1), p.116-121
• Main Authors: Xie, Yong, Zhang, Dongmao, Jarori, Gotam K., Davisson, V.Jo, Ben-Amotz, Dor
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Humans; Molecular Sequence Data; Oncogene Protein pp60(v-src) - chemistry; Oncogene Protein pp60(v-src) - metabolism; Peptide Fragments - chemistry; Peptide Fragments - metabolism; Peptides; Phosphorylation; Raman; Spectrum Analysis, Raman - methods; Src; Tyrosine; Tyrosine - metabolism
• ISSN: 0003-2697; 1096-0309
• DOI: 10.1016/j.ab.2004.05.052

Drop-coating-deposition-Raman (DCDR) is used to detect spectral changes induced by phosphorylation of tyrosine amino acid residues in peptides. Four peptides are investigated, with sequences derived from the human protein-tyrosine kinase, p60c-src, with Y-216, Y-419, and Y-530 phosphorylation sites. Although the spectra of the four peptides are quite different, tyrosine phosphorylation is found to invariably induce the collapse of a doublet at 820–850 cm −1 and the attenuation of a peak around 1205 cm −1. Moreover, amide III band shifts suggest that tyrosine phosphorylation may promote β sheet formation, particularly in peptides that lack phenylalanine residues. The degree of tyrosine phosphorylation in peptide mixtures is determined using DCDR combined with partial least squares multivariate calibration with a 2% root mean standard error of prediction.