演題概要

ポスター発表

第2日 6月18日(木)  P会場

リン酸化の同定と定量:Ser/Thrキナーゼ処理した合成ペプチドでの試み

(1阪大蛋白研2阪大院理3CIGB)
o汪秋益1石田一馬2安東友繁1Femandez-de-cossio, Jorge3柿本辰男2高尾敏文1

Usual phosphorylation of a protein proceeds enzymatically to add phosphate group(s) to the hydroxy group(s) at Ser/Thr/Tyr residues. In case of multiple sites of phosphorylation being found in a protein, it is required not only to identify the sites of phosphorylation, but also to quantify the degree of phosphorylation at each site. We report here a typical example of the analysis of multiple phosphorylation sites by using a synthetic peptide treated with a Ser/Thr-kinase derived from Arabidopsis thaliana. Following identification of the phosphorylation sites of the reaction product by MS/MS, it was subjected to LC-MS for relative quantification of phosphorylation at each site. We will also present the usefulness of an in-house software “Isomatch-Web” for identification of phosphorylation sites.