Preliminary Insights of Brazilian Snake Venom Metalloproteomics

Snakebite envenoming is one of the most significantly neglected tropical diseases in the world. The lack of diagnosis/prognosis methods for snakebite is one of our motivations to develop innovative technological solutions for Brazilian health. The objective of this work was to evaluate the protein and metallic ion composition of Crotalus durissus terrificus, Bothrops jararaca, B. alternatus, B. jararacussu, B. moojeni, B. pauloensis, and Lachesis muta muta snake venoms. Brazilian snake venoms were subjected to the shotgun proteomic approach using mass spectrometry, and metal ion analysis was performed by atomic spectrometry. Shotgun proteomics has shown three abundant toxin classes (PLA₂, serine proteases, and metalloproteinases) in all snake venoms, and metallic ions analysis has evidenced that the Cu²⁺ ion is present exclusively in the L. m. muta venom; Ca²⁺ and Mg²⁺ ions have shown a statistical difference between the species of Bothrops and Crotalus genus, whereas the Zn²⁺ ion presented a statistical difference among all species studied in this work. In addition, Mg²⁺ ions have shown 42 times more in the C. d. terrificus venom when compared to the average concentration in the other genera. Though metal ions are a minor fraction of snake venoms, several venom toxins depend on them. We believe that these non-protein fractions are capable of assisting in the development of unprecedented diagnostic devices for Brazilian snakebites.