This project reports the identification and characterization of saprophyticin S (SapS), a novel leaderless bacteriocin produced by Staphylococcus saprophyticus P1CEA4, a strain isolated from the porcine gastrointestinal tract. MALDI-TOF MS analysis revealed SapS variants corresponding to formylated and oxidized isoforms. To validate peptide identity, the active FPLC fraction was digested with trypsin and analyzed by LC-MS/MS. Proteome Discoverer 2.4 (Mascot search) initially provided 16% sequence coverage, while PEAKS Studio 10.5 improved coverage to 78%, identifying multiple peptides consistent with the predicted SapS sequence. These results provide strong proteomic evidence for SapS production in the native strain and support subsequent functional and structural characterization. The dataset contains processed outputs (Excel and HTML files) from Proteome Discoverer and PEAKS analysis, including peptide identifications, scores, probabilities, PTMs, and coverage statistics.