Design, synthesis, and evaluation of Bothrops venom serine protease peptidic inhibitors

 

Gloria Maria da Silva1, Daniel Henrique Berto de Souza1, Karoline B. Waitman1, Matteo Celano Ebram1, Melissa R. Fessel2, Iuliu Cezar Zainescu3, Fernanda C. Portaro4, Montse Heras5, Sonia A. de Andrade1

 

1 Laboratory of Pain and Signaling, Butantan Institute, São Paulo, SP, Brazil.

2 Laboratory of Molecular Biology, Butantan Institute, São Paulo, SP, Brazil.

3 Department of Chemistry, University of Oxford, Oxford, United Kingdom.

4 Laboratory of Immunochemistry, Butantan Institute, São Paulo, SP, Brazil.

5 Laboratory of Innovation in Processes and Products of Organic Synthesis, Department of Chemistry, University of Girona, Montilivi Campus, Girona, Spain.

 

Abstract

Background: In Central and South America, snakebite envenomation is mainly caused by Bothrops spp. snakes, whose venoms feature significant biochemical richness, including serine proteases. The available bothropic antivenoms are efficient in avoiding fatalities, but do not completely neutralize venom serine proteases, which are co-responsible for some disorders observed during envenomation.

 

Methods: In order to search for tools to improve the antivenom’s, 6-mer peptides were designed based on a specific substrate for Bothrops jararaca venom serine proteases, and then synthesized, with the intention to selectively inhibit these enzymes.

 

Results: Using batroxobin as a snake venom serine protease model, two structurally similar inhibitor peptides were identified. When tested on B. jararaca venom, one of the new inhibitors displayed a good potential to inhibit the activity of the venom serine proteases. These inhibitors do not affect human serine proteases as human factor Xa and thrombin, due to their selectivity.

 

Conclusion: Our study identified two small peptides able to inhibit bothropic serine proteases, but not human ones, can be used as tools to enhance knowledge of the venom composition and function. Moreover, one promising peptide (pepC) was identified that can be explored in the search for improving Bothrops spp. envenomation treatment.

 

Keywords: Peptides Snake venom Serine protease Disease Hemostasis

 

Correspondence: sonia.andrade@butantan.gov.br

 

Received: 07 May 2020; Accepted: 12 December 2020; Published online: 15 January 2021.