title: Bioconjugates for tunable peptide fragmentation: free radical initiated peptide sequencing (FRIPS).
abstract: The free radical initiator Vazo 68 is coupled to a peptide and electrosprayed into an ion trap mass spectrometer. On collisional activation, the Vazo 68-peptide conjugate generates a free radical, which can be collisionally activated to cleave the peptide backbone. Mostly z-type fragments are formed, as in CAD of other radical peptides and ECD fragmentation. We present data for the Angiotensin II-Vazo 68 conjugate and discuss possible sites of H atom abstraction from the peptide. This experimental methodology for generating peptide fragments is a useful step toward the development of a completely gas-phase approach to protein sequencing.
authors.affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Hodyss
authors.forename: Heather A
authors.initials: HA
authors.lastname: Cox
authors.forename: J L
authors.initials: JL
authors.lastname: Beauchamp
mesh_terms: D000804:Angiotensin II / Q000138:chemical synthesis* / Q000737:chemistry; D001391:Azo Compounds / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry; D009930:Organic Chemicals / Q000138:chemical synthesis* / Q000737:chemistry; D010446:Peptide Fragments / Q000138:chemical synthesis* / Q000737:chemistry; D020539:Sequence Analysis, Protein / Q000379:methods*
chemical_list: D001391:Azo Compounds; D005609:Free Radicals; D009570:Nitriles; D009930:Organic Chemicals; D010446:Peptide Fragments; C507291:Vazo 68; D000804:Angiotensin II