Phosphoproteins mass spectrometry protocol

A general protocol for mass spectrometric analysis of phosphoproteins is illustrated in Figure 15 various steps of this protocol are cleavage of purified phosphoproteins, isolation and preferential enrichment of phosphopeptides, selective detection of phosphopeptides in the digest, identification of the phosphorylation sites using tandem mass spectrometry, and identification of phosphopeptides/proteins through a database search. 

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