Assessing the Genetic Diversity of Ilex guayusa Loes., a Medicinal Plant from the Ecuadorian Amazon

Ilex guayusa Loes. is a shrub native to the Neotropics, traditionally consumed as an infusion. Despite its cultural value and extensive use, genetic research remains scarce. This study examined the genetic and clonal diversity of guayusa in three different Ecuadorian Amazon regions using 17 species-specific SSR markers. The results obtained suggest a moderately low degree of genetic diversity (He = 0.396). Among the 88 samples studied, 71 unique multilocus genotypes (MLGs) were identified, demonstrating a high genotypic diversity. A Discriminant Analysis of Principal Components (DAPC) revealed the existence of two genetic clusters. We propose that a model of isolation-by-environment (IBE) could explain the genetic differentiation between these clusters, with the main variables shaping the population’s genetic structure being temperature seasonality (SD × 100) (Bio 4) and isothermality ×100 (Bio 3). Nonetheless, we cannot dismiss the possibility that human activities could also impact the genetic diversity and distribution of this species. This study gives a first glance at the genetic diversity of I. guayusa in the Ecuadorian Amazon. It could assist in developing successful conservation and breeding programs, which could promote the economic growth of local communities and reinforce the value of ancestral knowledge

Antibacterial and antiviral properties of Chenopodin-derived synthetic peptides

Antimicrobial peptides have been developed based on plant-derived molecular scaffolds for the treatment of infectious diseases. Chenopodin is an abundant seed storage protein in quinoa, an An-dean plant with high nutritional and therapeutic properties. Here, we used computer- and physico-chemical-based strategies and designed four peptides derived from the primary structure of Che-nopodin. Two peptides reproduce natural fragments of 14 amino acids from Chenopodin, named Chen1 and Chen2 and two engineered peptides of the same length were designed based on the Chen1 sequence. The two amino acids of Chen1 containing amide side chains were replaced by ar-ginine (ChenR) or tryptophan (ChenW) to generate engineered cationic and hydrophobic peptides. The evaluation of these 14-mer peptides on Staphylococcus aureus and Escherichia coli showed that Chen1 does not have antibacterial activity up to 512 µM against these strains, while other peptides exhibited antibacterial effects at lower concentrations. The chemical substitutions of glutamine and asparagine by amino acids with cationic or aromatic side chains significantly favoured their antibacterial effects. These peptides did not show significant hemolytic activity. Fluorescence mi-croscopy analysis highlighted the membranolytic nature of Chenopodin-derived peptides. Using molecular dynamic simulations, we found that a pore is formed when multiple peptides are as-sembled in the membrane. Whereas some of them form secondary structures when interacting with the membrane, allowing water translocations during the simulations. Finally, Chen2 and ChenR significantly reduced SARS-CoV-2 infection. These findings demonstrate that Chenopodin is a highly useful template for design, engineering, and manufacturing of non-toxic, antibacterial, and antiviral peptides