title: Sequencing Lys-N proteolytic peptides by ESI and MALDI tandem mass spectrometry.
abstract: In this study, we explored the MS/MS behavior of various synthetic peptides that possess a lysine residue at the N-terminal position. These peptides were designed to mimic peptides produced upon proteolysis by the Lys-N enzyme, a metalloendopeptidase issued from a Japanese fungus Grifola frondosa that was recently investigated in proteomic studies as an alternative to trypsin digestion, as a specific cleavage at the amide X-Lys chain is obtained that provides N-terminal lysine peptide fragments. In contrast to tryptic peptides exhibiting a lysine or arginine residue solely at the C-terminal position, and are thus devoid of such basic amino acids within the sequence, these Lys-N proteolytic peptides can contain the highly basic arginine residue anywhere within the peptide chain. The fragmentation patterns of such sequences with the ESI-QqTOF and MALDI-TOF/TOF mass spectrometers commonly used in proteomic bottom-up experiments were investigated.
authors.affiliation: Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS-Universités Montpellier 1 et 2, Bâtiment Chimie (17), Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Dupré
authors.forename: Sonia
authors.initials: S
authors.lastname: Cantel
authors.forename: Pascal
authors.initials: P
authors.lastname: Verdié
authors.forename: Jean
authors.initials: J
authors.lastname: Martinez
authors.forename: Christine
authors.initials: C
authors.lastname: Enjalbal
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D008666:Metalloendopeptidases / Q000378:metabolism; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism; D020539:Sequence Analysis, Protein / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D000596:Amino Acids; D010446:Peptide Fragments; D008666:Metalloendopeptidases