title: Photodissociation of charge tagged peptides.
abstract: Tris(2,4,6-trimethoxyphenyl) phosphonium acetyl (TMPP-Ac) was previously introduced to improve the mass spectrometric sequence analysis of peptides by fixing a permanent charge at the N-termini. However, peptides containing arginine residues did not fragment efficiently after TMPP-Ac modification. In this work, we combine charge derivatization with photodissociation. The fragmentation of TMPP-derivatized peptides is greatly improved and a series of N-terminal fragments is generated with complete sequence information. Arginine has a special effect on the fragmentation of the TMPP tagged peptides when it is the N-terminal peptide residue. Theoretical and experimental results suggest that this is due to hydrogen transfer from the charged N-terminus to the hydrogen-deficient peptide sequence.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, IN 47405, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: He
authors.forename: Ramakrishnan
authors.initials: R
authors.lastname: Parthasarathi
authors.forename: Krishnan
authors.initials: K
authors.lastname: Raghavachari
authors.forename: James P
authors.initials: JP
authors.lastname: Reilly
mesh_terms: D000595:Amino Acid Sequence; D001120:Arginine / Q000737:chemistry; D006859:Hydrogen; D007477:Ions / Q000737:chemistry; D008239:Lysine / Q000737:chemistry; D008969:Molecular Sequence Data; D009943:Organophosphorus Compounds / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D055668:Photochemical Processes; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D007477:Ions; D009943:Organophosphorus Compounds; D010455:Peptides; C405845:tris(trimethoxyphenyl)phosphonium acetyl; D006859:Hydrogen; D001120:Arginine; D008239:Lysine