N-terminal Sequencing

In protein N-terminal sequence analysis, proteins are first modified with phenylisothiocyanate (PITC). This method can sequence the whole amino acid from the N-terminal end. Compared with mass spectrometer, N-terminal Edman sequencing seems less efficient, but it still has advantages for protein analysis that cannot readily be obtained by other analysis methods. With current technology in creative proteomics, it is fairly routine to obtain at least 20 to 25 residues of sequence from the N-terminus of the proteins and peptides.