Metabolic characterization of microfungi associated with leaf-cutting ants (Hymenoptera: Formicidae)

Abstract

Leaf-cutting ants maintain an obligatory association with mutualistic fungi cultivated for food. In addition to the ant fungus several microbes were found in the fungus-gardens of these insects, including microfungi (yeasts and filamentous fungi). Little is known about the putative roles of such microorganisms in this insect-fungus interaction. Due to the ability of microfungi to produce hydrolytic enzymes, it is suggested that such microbes help to metabolize the plant substrate used for culturing the mutualistic fungus. Here, we aim to assess the enzymatic profile of microfungi isolated from leaf-cutting ant species with display different foraging behaviors, Atta sexdens rubropilosa (a dicot-cutting ant) and Atta capiguara (a grass-cutting ant). Microfungi will be isolated from fungus-gardens and screened for the following enzymes: cellulase, amylases, xylanases, pectinases and polygalacturonases. The comparison of the enzymatic profiles of microfungi isolated from each ant group of (dicot x grass-cutting) will be evaluated in order to advance in the understanding of the roles of such microorganisms in the gardens. It is possible that ant with different foraging habits present microfungi with different enzymatic profiles. Moreover, microfungal isolates that produce a broad spectrum of the tested enzymes will be used for in vitro assays to verify if culture extracts of microfungi influence the growth of the mutualistic fungus. This study will contribute to increase Institute of Biosciences -Culture Collection with the deposit of taxonomically authentic fungal strains with biotechnological potential.