title: De novo sequencing of peptides on single resin beads by MALDI-FTICR tandem mass spectrometry.
abstract: An efficient approach in combinatorial chemistry is the synthesis of one-bead-one-compound peptide libraries. In contrast to synthesis and functional screening, which is performed in a largely automated manner, structure determination has been frequently laborious and time-consuming. Here we report an approach for de novo sequencing of peptides on single beads by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance (MALDI-FTICR) tandem mass spectrometry, using a resin with a photolinker for solid-phase peptide synthesis. Upon sorting out single beads, an efficient sample preparation on the MALDI target was developed that enables fragmentation upon irradiation of the bead-matrix mixture with the ultraviolet (UV)-MALDI laser, with enhanced yield of sequence-specific fragment ions at increased laser energy. This approach is illustrated by sequence determinations of two peptides from a library with sequences varying in a single amino acid; the feasibility with tandem-MS procedures and fragment ion assignment was ascertained by sustained off-resonance irradiation/collision induced dissociation (SORI/CID) and infrared multiphoton dissociation (IRMPD) fragmentation.
authors.affiliation: Laboratory of Bioorganic Chemistry, Department of Chemistry, University of Konstanz, Konstanz, Germany.
authors.forename: Angelika
authors.initials: A
authors.lastname: Semmler
authors.forename: Reinhold
authors.initials: R
authors.lastname: Weber
authors.forename: Michael
authors.initials: M
authors.lastname: Przybylski
authors.forename: Valentin
authors.initials: V
authors.lastname: Wittmann
mesh_terms: D005583:Fourier Analysis; D019151:Peptide Library; D010455:Peptides / Q000032:analysis / Q000737:chemistry*; D020539:Sequence Analysis, Protein / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D019151:Peptide Library; D010455:Peptides