Heterologous expression of Ts8, a neurotoxin from Tityus serrulatus venom, evidences its antifungal activity

Author(s)

Cordeiro, Francielle Almeida ; Amorim, Fernanda Gobbi ; Boldrini-Franca, Johara ; Pinheiro-Junior, Ernesto Lopes ; Cardoso, Iara Aime ; Zoccal, Karina Furlani ; Peigneur, Steve ; Faccioli, Lucia Helena ; Tytgat, Jan ; Arantes, Eliane Candiani

• Document type: Journal article
• Source: Toxicon; v. 218, p. 10-pg., 2022-09-13.

Abstract

In this study we expressed the Ts8, a neurotoxin from Tityus serrulatus scorpion venom, in Pichia pastoris yeast. We evaluated the peptide expression in different conditions, such as pH, temperature, and addition of casamino acids supplement. Analyses of expressed products by mass spectrometry and Edman degradation showed that rTs8 has sites that allow its cleavage by yeast proteases released into the culture medium. The casamino acids addition was favourable for toxin expression, however, was not sufficient to minimize proteolytic degradation. Functional assays with recombinant toxin fragments and native toxins have demonstrated the release of cytokines such as TNF-alpha and IL-1 beta in some peptides tested. In addition, the toxins were shown to inhibit the Pichia pastoris growth in antifungal test and were not toxic to alveolar macrophages cells at the concentrations analyzed The electrophysiological screening, by voltage clamp technique, showed that the rTs8 fragment with the highest molecular weight inhibited the Kv1.3 channel, whereas the N-terminal fragment had no activity on the ion channels tested. (AU)

• FAPESP's process: 16/04761-4 - Functional and structural characterization and immune response evaluation of a recombinant serine protease from Crotalus durissus collilineatus modified by PEGylation
• Grantee: Ernesto Lopes Pinheiro Junior
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)