Sphingomyelinase D Activity in Sicarius tropicus Venom: Toxic Potential and Clues to the Evolution of SMases D in the Sicariidae Family

Author(s)

Lopes, Priscila Hess ^[1] ; Fukushima, Caroline Sayuri ^{[2, 3]} ; Shoji, Rosana ^[1] ; Bertani, Rogerio ^[3] ; Tambourgi, V, Denise

Affiliation

^[1] V, Butantan Inst, Immunochem Lab, BR-05503900 Sao Paulo - Brazil

^[2] Univ Helsinki, Finnish Museum Nat Hist, Helsinki 00014 - Finland

^[3] Butantan Inst, Special Lab Ecol & Evolut, BR-05503900 Sao Paulo - Brazil

• Document type: Journal article
• Source: TOXINS; v. 13, n. 4 APR 2021.
• Web of Science Citations: 0

Abstract

The spider family Sicariidae includes three genera, Hexophthalma, Sicarius and Loxosceles. The three genera share a common characteristic in their venoms: the presence of Sphingomyelinases D (SMase D). SMases D are considered the toxins that cause the main pathological effects of the Loxosceles venom, that is, those responsible for the development of loxoscelism. Some studies have shown that Sicarius spiders have less or undetectable SMase D activity in their venoms, when compared to Hexophthalma. In contrast, our group has shown that Sicarius ornatus, a Brazilian species, has active SMase D and toxic potential to envenomation. However, few species of Sicarius have been characterized for their toxic potential. In order to contribute to a better understanding about the toxicity of Sicarius venoms, the aim of this study was to characterize the toxic properties of male and female venoms from Sicarius tropicus and compare them with that from Loxosceles laeta, one of the most toxic Loxosceles venoms. We show here that S. tropicus venom presents active SMases D. However, regarding hemolysis development, it seems that these toxins in this species present different molecular mechanisms of action than that described for Loxosceles venoms, whereas it is similar to those present in bacteria containing SMase D. Besides, our results also suggest that, in addition to the interspecific differences, intraspecific variations in the venoms' composition may play a role in the toxic potential of venoms from Sicarius species. (AU)

• FAPESP's process: 15/17053-5 - Study of inflamassomes activation, in human keratinocytes, by Loxosceles laeta spider venom and its sphingomyelinase D
• Grantee: Priscila Hess Lopes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/07467-1 - CeTICS - Center of Toxins, Immune-Response and Cell Signaling
• Grantee: Hugo Aguirre Armelin
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC