In vitro testing of antimicrobial peptides from three species of the genus Cereus for applications in human health and agriculture.

• Grant number: 25/17270-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: January 01, 2026
• End date: December 31, 2028
• Field of knowledge: Biological Sciences - Biochemistry
• Principal Investigator: Danilo Trabuco do Amaral
• Grantee: João Alfredo Teodoro
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Santo André , SP, Brazil
• Associated research grant: 23/05589-4 - Metabolic pathways and gene product bioprospection in mandacaru species (Cactaceae) for biotechnological purposes: exploring popular knowledge using omics technologies, AP.R

Abstract

Mandacaru is a widely known cactus species in Brazil, with applications in the medicinal, food, and agricultural fields. However, its biotechnological potential remains underexplored, especially regarding its antimicrobial properties. Given the growing resistance of pathogens to conventional antimicrobials, there is increasing interest in discovering new bioactive compounds of plant origin. Previous studies using in silico bioprospecting investigated antimicrobial peptides (AMPs) in three species of the Cactaceae family (Cereus fernambucensis, C. hildmannianus, and C. jamacaru), identifying four promising AMPs-two in C. fernambucensis and two in C. hildmannianus. These peptides show potential for therapeutic applications in both human health and agriculture. This project proposes the synthesis and expression of these AMPs in heterologous systems using Escherichia coli and the microalga Chlamydomonas reinhardtii, due to their widespread use, low cost, and ability to produce complex recombinant proteins. Structural validation will be performed through mass spectrometry (MS), enabling accurate identification of the expressed peptide sequences. Following purification, the peptides will be tested in vitro against microorganisms relevant to human and agricultural health. Subsequently, their stability and efficacy will be assessed under different environmental conditions, including variations in temperature, salinity, and pH. Finally, the interaction of the AMPs with metal ions and streptolidigin will be evaluated to investigate potential synergistic effects in microbial growth inhibition. The results will allow for a comprehensive evaluation of the antimicrobial potential and environmental stability of these peptides, contributing to future in vivo analyses. Additionally, this project aims to characterize sustainable, plant-derived compounds as promising alternatives in the fight against antimicrobial resistance. (AU)