서강대학교

초록/요약

Mass spectrometry (MS) is one of the most powerful tools in peptide sequencing. Among many methods for characterizing gas-phase peptides, the free radical initiated peptide sequencing (FRIPS), has been under spotlight because the method requires only collision induced dissociation (CID) conditions for the mass-fragmentation patterns similar to those obtained by the electron collision dissociation (ECD) method. Generally, the FRIPS technique demands introduction of a free-radical generating group into a peptide chain so that a radical species can be generated under CID conditions. We have recently reported a new FRIPS reagent based on (2,2,6,6- tetramethylpiperidine-1-oxy)-(TEMPO) capped benzyl groups and demonstrated that it worked successfully. As an extension of the study, we have synthesized a series of reagents with different substituents at the para-position of the benzoate and obtained FRIPS data of various peptides using these reagents in series. This chapter will discuss the relationship between the constitution of the radical and the peptide fragmentation pattern, and collision energy for the radical species generated.