Updated publication reference for PubMed record(s): 25452133. Serine proteinases have been shown to play the role of toxins in the venoms of many snakes. They act mainly on components of the coagulation cascade, and fibrinolytic and kallikrein-kinin systems to trigger various pathological effects observed in the envenomation. Despite showing high similarity in terms of primary structure snake venom serine proteinases (SVSPs) show exquisite specificity towards macromolecular substrates. Therefore, the characterization of their peptide bond specificity is important for understanding the active site preference associated with effective proteolysis as well as for the design of peptide substrates and inhibitors. Bothrops jararaca contains various SVSPs among which Bothrops protease A (BPA) is a specific fibrinogenolytic agent and PA-BJ is a platelet-activating enzyme. In this study we used proteome derived peptide libraries in the Proteomic Identification of protease Cleavage Sites (PICS) approach to explore the peptide bond specificity of BPA and PA-BJ in order to determine their individual peptide cleavage sequences. A total of 371 cleavage sites (208 for BPA and 163 for PA-BJ) were detected and both proteinases displayed a clear preference for arginine at the P1 position. Moreover, the analysis of the specificity profiles of BPA and PA-BJ revealed subtle differences in the preferences along P6-P6’, despite a common preference for Pro at P2. Taken together, these results illustrate the subsite specificity of both SVSPs and shed light in the functional differences between these proteinases.