Search for new enzymatic inhibitors of cathepsins in extracts obtained from fungi associated with leaf cutting ants nest

Abstract

The microorganisms associated with leaf-cutting ants nests provide unique opportunities to exploit natural antifungal and insecticidal agents due to the microbial networks they are involved. Leaf-cutting ants' fungal garden comprises a complex microbial network in which participate, at least, a mutualist fungus (Leucoagaricus gongylophorus), a specialized parasite (Escovopsis), symbiont actinomycetes (Pseudonocardia and Streptomyces) and other microorganisms with unknown ecological relationship. Due to the chemical mediators utilized in this network to establish the virulence or defense factors, microorganisms living in leaf-cutting ants' fungal garden are potential producers of antimicrobial substances. Fungi belonging to the genus Escovopsis are parasites of the ants' fungal gardens and can destroy them completely causing nest death. After several studies, researchers showed that Escovopsis secretes antifungal substances that break down L. gongylophorus mycelium. Therefore, this genus represents an important producer of antifungal and biocontrol agents for leaf-cutting ants. To protect the fungal garden against virulent Escovopsis and to preclude nest death, microbial ants symbionts, especially Pseudonocardia species, produce antifungal compounds. However, the basis of this synergism still remains unknown. Despite these environmental and scientific observations, no efforts have been carried out aiming to elucidate the bioactive mediators that are being produced by Escovopsis. Thus, this work plan aims to progress in the studies of chemical and chemical-ecology aspects of E. weberi, associated to leaf-cutting ants fungal garden. Metabolomic, spectroscopic, antifungical and enzymatics studies must be performed to give a best formation to student Priscila Lopes.