Mass spectrometry analysis of Schwann cell-derived neurotrophic protein / 中华显微外科杂志

ABSTRACT

Objective To analyse the molecular structure of Schwann cell derived neurotrophic protein (SDNP) by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF MS) Methods The purity of SDNP was digested byTPCK trypsin and detected by MALDI TOF MS, mass mapping was determined and partial sequences of the protein have neen analyzed by the mass data of fragment ion peaks in the fragmentation analysis and structural TOF MS (FAST) spectra The primary partial structure of SDNP was identified by searching the protein databases Results The integrity SDNP in peak detected by MALDI TOF MS has 66?10 3 MW and higher purity, because no other peaks exists except double charge peak The mass mapping of many peptides was determined and 8 peptides of them have been retrieved in MS Fit database, there is not the same protein in database Hypothetical protein has 5 peptides homology with the sample (62%) FAST spectra of 2305 Da shows the primary partial structure of SDNP after searching the protein MS Tag database Conclusions The molecular weight of SDNP detected by MALDI TOF MS is 66?10 3, The sequence of partial amino acid is EPVKKVTNSRRAKRTKPNGHIAN