Ricerc@Sapienza

Short peptides are of extreme interest in food research, due to their wide range of biological activity they are well-known to exert. However, they still represent an often unresolved analytical issue. The main aim of this project is the development of an analytical platform for a considerable advancement in short peptides identification. For the first time, short sequences presenting both natural and post-translationally modified amino acids are going to be comprehensively studied, with a particular attention to extraction, purification, data acquisition, and compound identification. Data acquisition and compound identification are the most critical aspects, as the standard technologies borrowed from proteomics are not efficient for short peptide sequences. For this purpose, specific short peptide databases can be generated. Short peptide databases will have a dual purpose. First, they will be employed as inclusion list for a suspect screening mass-spectrometric analysis, overcoming the limits of data-dependent acquisition mode and allowing the fragmentation of such low-abundance substances. Moreover, the databases will be implemented in Compound Discoverer 3.1, a software dedicated to the analysis of short molecules, for the creation of a data processing workflow specifically dedicated to short peptide identification. For this purpose, a detailed study of short peptide fragmentation pathways will be carried out for the first time, with the purpose of elucidating the differences between natural and modified short peptide sequences and the highly studied medium-sized tryptic peptides.