Venom composition of the Iberian adder (Vipera seoanei) from northern Portugal reveals limited sex and size variation

  Venom composition of the Iberian adder (Vipera seoanei) from northern Portugal reveals limited sex and size variation Abstract Snake venom is a complex and dynamic ecological trait, with high potential for intraspecific variation. In this study, the venom composition of the Iberian adder ( Vipera seoanei ) from the Peneda Mountains of northern Portugal was investigated to explore whether venom varies with body size and sex. Venom proteomes from six individuals representing juvenile, subadult, and adult males and females were characterised using LC–MS/MS, while individual variation was assessed from SDS–PAGE profiles of 18 snakes. LC–MS/MS identified 144 proteins, dominated by phospholipases A 2 (PLA 2 ), snake venom serine proteases (svSP), and C-type lectin-related proteins (CTL). Descriptive comparisons revealed contrasting individual profiles, particularly between the juvenile male, characterised by high svSP and svMP abundance, and the juvenile female, characterised by high ...

Pioneering Comparative Proteomic and Enzymatic Profiling of Amazonian Scorpion Venoms Enables the Isolation of Their First α-Ktx, Metalloprotease, and Phospholipase A2

 


Pioneering Comparative Proteomic and Enzymatic Profiling of Amazonian Scorpion Venoms Enables the Isolation of Their First α-Ktx, Metalloprotease, and Phospholipase A2

Abstract

Scorpionism is a growing public health concern in Brazil, with the Amazon region presenting the highest mortality rates but remaining understudied, especially regarding local scorpion venoms composition. This study presents the first comprehensive biochemical characterization of venoms from three Amazonian species—Tityus metuendus (TmetuV), Tityus silvestris (TsilvV), and Brotheas amazonicus (BamazV)—using an integrated approach combining Multi-Enzymatic Limited Digestion (MELD)-based bottom-up proteomics, high-resolution LC-MS/MS, chromatography, zymography, and enzymatic assays. Tityus serrulatus venom was included as a reference. Significant biochemical differences were observed: TsilvV was rich in 20–30 kDa proteins and showed strong metalloprotease activity; BamazV exhibited high molecular weight proteins and potent phospholipase A2 (PLA2) activity but lacked proteolytic and fibrinogenolytic activities; TmetuV showed the highest hyaluronidase activity and abundance of α-KTx neurotoxins. Zymography revealed a conserved ~45 kDa hyaluronidase in all species. Three novel components were partially characterized: BamazPLA2 (Group III PLA2), Tmetu1 (37-residue α-KTx), and TsilvMP_A (a metalloprotease homologous to antarease). This is the first application of MELD-based proteomics to Amazonian scorpion venoms, revealing molecular diversity and functional divergence within Tityus and Brotheas, emphasizing the need for region-specific antivenoms. These findings provide a foundation for future pharmacological studies and the discovery of bioactive peptides with therapeutic potential.

Bordon KCF, Santos GC, Martins JG, Wiezel GA, Amorim FG, Crasset T, Redureau D, Quinton L, Procópio REL, Arantes EC. Pioneering Comparative Proteomic and Enzymatic Profiling of Amazonian Scorpion Venoms Enables the Isolation of Their First α-Ktx, Metalloprotease, and Phospholipase A2. Toxins. 2025; 17(8):411. https://doi.org/10.3390/toxins17080411