Detection of the site of phosphorylation in a peptide using Raman spectroscopy and partial least squares discriminant analysis.
Normal (non-enhanced) Raman spectroscopy is used to determine the site of phosphorylation on a 13-residue peptide whose sequence derives from the cellular protein pp60(c-src) (protein tyrosine kinase). Raman spectra of serine, threonine and tyrosine amino acids and their phosphorylated derivatives are used to aid in the interpretation of peptide spectra. The purity of the synthetic peptides are confirmed by mass spectroscopy. Peptide Raman measurements are performed using the recently reported drop-coating deposition Raman (DCDR) method, followed by Savistky-Golay second derivative (SGSD) pre-processing and multivariate spectral classification using partial least squares (PLS) discriminant analysis. Leave-one-out training/testing results are displayed using a PLS psuedo-probability score plot and shown to facilitate error-free spectral determination of the site of phosphorylation.
Zhang
Dongmao
D
Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
Ortiz
Corasi
C
Xie
Yong
Y
Davisson
V Jo
VJ
Ben-Amotz
Dor
D
D006801:Humans; D015688:Oncogene Protein pp60(v-src) / Q000737:chemistry / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D012694:Serine / Q000378:metabolism*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013912:Threonine / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
D010446:Peptide Fragments; D013912:Threonine; D014443:Tyrosine; D012694:Serine; D015688:Oncogene Protein pp60(v-src)