Selective labeling agent for phosphoproteome analysis and phosphorylated site analysis

摘要: Disclosed is a method of analyzing mass the phosphoproteins or phosphopeptides and phosphorylated positions at phosphoprotein phosphopeptide, comprising steps of: 1) dephosphorylating least one Ser and/or Thr residue phosphopeptide; 2) tagging dephosphorylated amino acid residues with tag having R-L-G moiety wherein R nucleophilic functional group that selectively bind residues, G selected from consisting guanidine protected such as mono-N-protected guanidino group, di-N,N'-protected an N'-protected L linker linking G; 3) subjecting tagged proteins peptides to spectrometry. The capable precisely trace amounts well phosphoryated acids.