Synthesis, characterization and activity of peptide analogues of the (p-BthTX-I)

• Grant number: 19/24971-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2020
• End date: March 20, 2022
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Eduardo Maffud Cilli
• Grantee: Natália Vitória Bitencourt
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 13/07600-3 - CIBFar - Center for Innovation in Biodiversity and Drug Discovery, AP.CEPID

Abstract

The excessive and inappropriate use of antibiotics has led to the emergence of bacterial strains resistant to several of these molecules. The Center for Disease Control and Prevention stated that in this context, common infections and minor injuries will kill several people - post-antibiotic era. One strategy to circumvent these circumstances is the development of new effective molecules against multidrug resistant bacteria, among which stand out antimicrobial peptides (PAMs), found mainly in animal poisons. These are highly effective against multidrug resistant bacteria due to their mechanism of action, which makes it difficult for bacteria to acquire resistance. A peptide obtained from the C-terminal region of homologous phospholipase A2, p-Bothropstoxin I (BthTX-I), present in Bothrops jararacussu toxin, showed activity against multi-resistant bacteria in previous studies, mainly in its dimeric form. In addition, it showed action only in prokaryotic cells and was unable to form pores or rupture lipid vesicles, showing that this is not their form of action. In this project, aiming to obtain more active analogs, it is intended to perform the synthesis and evaluation of the peptide in the form of tetramer and octamer. The synthesis of the peptide in its stereo isomeric form D will also be performed to prove whether its mechanism of action is through bacterial membrane receptors that depend on its spatial structure. We hope with this information to contribute to understanding the mode of action of the peptide (p-BthTX-I) and to obtain more active analogs.