Tyrosine phosphorylation-induced changes in absorption and UV resonance Raman spectra of Src-peptides

✍ Scribed by Nobuyuki Okishio; Ryuji Fukuda; Masako Nagai; Yukifumi Nagai; Shigenori Nagatomo; Teizo Kitagawa

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 520 KB
• Volume: 29
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/(sici)1097-4555(199801)29:1<31::aid-jrs208>3.0.co;2-b

✦ Synopsis

To elucidate possible conformational changes of proteins induced by tyrosine phosphorylation, the phosphorylationinduced changes in the absorption and UV resonance Raman (UVRR) spectra of the two kinds of 13-residue peptides in pp60cvsrc protein containing either Tyr416 (autophosphorylation site) or Tyr527 (C-terminal phosphorylation site) were investigated and compared with the changes for free L-tyrosine. Phosphorylation caused a blue shift and a marked decrease in the 275 nm absorption band transition) for both peptides and L-tyrosine. In (L b the UVRR spectra, although wavenumber downshifts of several modes were observed upon phosphorylation, the most pronounced-change was the distinct intensity reduction of the Y1 band around 850 cm-1 and appearance of the Y13 band around 760 cm-1. These phosphorylation-induced changes were totally restored upon dephosphorylation with alkaline phosphatase. A Raman band characteristic of the Tyr527-peptide was also detected. A band at 1461 cm-1, which appeared regardless of the phosphorylation state, was assigned to amide IIp from comparison with the spectra of other peptides containing proline residues. The e †ects of H/D exchange on the UVRR spectra were also examined. This is the Ðrst application of UVRR spectroscopy to the detection of possible structural changes of the tyrosine residue on phosphorylation.