title: Discrimination of isobaric Leu/Ile residues by MALDI in-source decay mass spectrometry.
abstract: 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 z• radical fragments via α 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.
authors: Chemistry Department and GIGA-R, Mass Spectrometry Laboratory, University of Liege, Liege, Belgium. dasakawa@yokohama-cu.ac.jp
authors: Daiki
authors: D
authors: Asakawa
authors: Nicolas
authors: N
authors: Smargiasso
authors: Edwin
authors: E
authors: De Pauw
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000737:chemistry; D005841:Gentisates / Q000737:chemistry; D007532:Isoleucine / Q000032:analysis / Q000737:chemistry*; D007930:Leucine / Q000032:analysis / Q000737:chemistry*; D008958:Models, Molecular; D009211:Myoglobin / Q000737:chemistry; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D062367:ortho-Aminobenzoates / Q000737:chemistry
chemical_list: D005841:Gentisates; D009211:Myoglobin; D062367:ortho-Aminobenzoates; D007532:Isoleucine; C031385:anthranilic acid; C510889:1,5-diaminonaphthalene; D015081:2-Naphthylamine; D007930:Leucine; C010925:2,5-dihydroxybenzoic acid