title: Elucidating the sequence of intact bioactive peptides by using electron capture dissociation and hot electron capture dissociation in a linear radio-frequency quadrupole ion trap.
abstract: BACKGROUND
  Electron capture dissociation (ECD) is useful tool for sequencing of peptides and proteins with post-translational modifications. To increase the sequence coverage for peptides and proteins, it is important to develop ECD device with high fragmentation efficiency.
  
  
  METHODS
  Sequence analysis of intact undigested bioactive peptides (3000-5000 Da) was performed by use of electron capture dissociation (rf-ECD) and collision-induced dissociation (CID) in a linear radio-frequency quadrupole ion trap that was coupled to a time-of-flight mass spectrometer. We applied rf-ECD, hot rf-ECD (rf-ECD with high electron energy), and CID for intact bioactive peptide ions of various charge states and evaluated the sequence coverage of their fragment spectra.
  
  
  RESULTS
  Hot rf-ECD produced a higher number of c- and z-type fragment ions of modified peptide ions as electron energy increased in lower charged peptide ions, and sequence coverage greater than 80% was obtained compared with the CID case (40-80%).
  
  
  CONCLUSIONS
  The result indicates that intact bioactive modified peptides (Ghrelin, ANP) were correctly identified by use of hot rf-ECD.
authors.affiliation: Central Research Laboratory, Hitachi Ltd., 1-280 Higashi-koigakubo, Kokubunji-shi, 185-8601, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Satake
authors.forename: Naomi
authors.initials: N
authors.lastname: Manri
authors.forename: Akihito
authors.initials: A
authors.lastname: Kaneko
authors.forename: Atsumu
authors.initials: A
authors.lastname: Hirabayashi
authors.forename: Hideki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Baba
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Masuda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010455:Peptides / Q000737:chemistry* / Q000235:genetics; D011506:Proteins / Q000737:chemistry* / Q000235:genetics; D051381:Rats
chemical_list: D010455:Peptides; D011506:Proteins