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| Author(s): |
Bruno Duzzi
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) |
| Defense date: | 2014-05-27 |
| Examining board members: |
Vanessa Rioli;
Inácio de Loiola Meirelles Junqueira de Azevedo;
Vitor Marcelo Silveira Bueno Brandão de Oliveira
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| Advisor: | Vanessa Rioli; Fernanda Calheta Vieira Portaro |
| Abstract | |
The scorpion Tityus serrulatus is responsible for the most serious accidents in Brazil. Among the components already studied in its venom, neurotoxins are able to interact with ion channels, and peptides with biological activity are also present. In this study, peptides from low molecular weight fraction of the venom that interacted with the oligopeptidases thimet oligopeptidase (EP24.15) and neurolysin (EP24.16) were isolated using specific fluorescent substrates as a tool. Sequences from the peptides KEILG, FTR, YLPT and the analogue KELLG were determined by mass spectrometry and subsequently synthesized. In vitro, the peptides were not substrates for those enzymes, neither for neprilysin and ACE enzymes. Concerning inhibition, the highlights are the KELLG and KEILG, which were able to inhibit EP 24.15 but not EP 24.16. Another peptide thats worth to mention is YLPT, with a Ki of 0.94 mM for neprilysin. In vivo, the peptides were tested for nociception, rolling of leukocytes and vascular reactivity, being the FTR distinguished to be able to cause antinociceptive effect and KEILG to increase the number of leukocytes. These results emphasize the importance of small molecules in the scorpion venom constitution. (AU) | |
| FAPESP's process: | 11/15472-0 - Search for new substrates and / or inhibitors for EP24.15 and EP24.16 in the low molecular weight fractions of the Tityus serrulatus scorpion venom. |
| Grantee: | Bruno Duzzi |
| Support Opportunities: | Scholarships in Brazil - Master |