Characterization of Vipera seoanei venom, variation with species ontogeny and evaluation of its antimicrobial potential

• Autor(a) principal: Corga, Frederico Seiça Neves Ataíde e
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/36689
• topic: Vipera seoanei; Snake venom; Venom variation; Ontogenic shift; Antibacterial potential

The animal kingdom has approximately 200,000 toxin-producing species, used for both predation and defense. Venomous snakes produce venom composed of a mixture of proteins and peptides (90-95%), free amino acids, amines, nucleosides, metal ions, lipids, and carbohydrates. Those proteins and/or peptides are generally responsible for the toxicity of the venom, however these molecules have great potential for discovering new drugs. In the present study, we intended to evaluate the venom of Vipera seoanei from the population of Serra da Peneda/Laboreiro from different perspectives. In a first phase, analyze its composition at the proteomic level and later verify if there is ontogenic variation. In a second phase, to assess the antibacterial potential of this venom. For the proteomic analysis of the venom, a preliminary screening of the venom was carried out using SDS-PAGE, followed by LC-MS/MS. The possible antibacterial activity of the crude venom was tested by the Micro Broth dilution method, against the bacteria Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028, Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 25923. The results of the proteomics (LC-MS/MS) analysis show that the venom is essentially composed of Snake Venom Serine Proteases (SVSPs), Phospholipases A₂ (PLA₂s), C-type lectins (CTLs) e Snake Venom Metalloproteinases (SVMPs). Also, it shows that the venom varies at the ontogenic level, in which juveniles are characterized by a more abundant venom in K49 PLA₂s and SVSPs, while adults by Cysteine-rich secretory proteins (CRISPs). Also, the venom of subadults and adults is richer in CTL than juveniles. Crude venom was found to affect the growth of S. aureus from a concentration of 50 μg protein/mL or 200 μg venom/mL. In addition, and despite not having statistically significant differences, in higher concentrations of venom it is observed a tendency to impair the growth of the remaining tested bacteria. The results presented by the present study allowed to characterize the venom of a population of V. seoanei from Serra da Pena/Laboreiro, as well as to verify its variation in its composition due to ontogeny. Finally, it allowed to show the antimicrobial potential of this venom.