Discrimination of Isobaric Leu/Ile Residues by MALDI In-Source Decay Mass Spectrometry

作者：Asakawa Daiki^*; Smargiasso Nicolas; De Pauw Edwin

来源：Journal of the American Society for Mass Spectrometry, 2013, 24(2): 297-300.

DOI：10.1007/s13361-012-0523-7

• Initial velocity
• Side-chain loss
• 1,5-Diaminonapthalene
• Negative-ion mode
• Top-down sequencing

MALDI in-source decay (ISD) has been used for top-down sequencing of proteins. The use of the matrix 1,5-diaminonapthalene (1,5-DAN) gave abundant w ions, which are formed from the unimolecular dissociation of zaEuro cent radical fragments via alpha cleavage reaction and thus help identify which of the isobaric amino acids, Leu or Ile, is present. The high abundance of w ions in MALDI-ISD with 1,5-DAN results from the low collision rate in the MALDI plume. MALDI-ISD with 1,5-DAN appears to be an useful method for the top-down sequencing of proteins, including discrimination of Leu and Ile near the C-terminal end.

• 出版日期2013-2