Fungus gardens of leaf-cutting ants: Functional flexibility, metabolic complementarity, and biotechnological applications

• Grant number: 21/08013-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: February 01, 2022
• End date: March 31, 2024
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: André Rodrigues
• Grantee: Mariana de Oliveira Barcoto
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated research grant: 19/03746-0 - Collaborative research: Dimensions US-São Paulo: integrating phylogeny, genetics, and chemical ecology to unravel the tangled bank of the multipartite fungus-farming ant symbiosis, AP.BTA.TEM

Abstract

Fungus-growing ants in the subtribe Attina evolved an obligate association with basidiomycete fungi, cultivated in a sponge-like structure known as fungus garden. The symbiotic fungus converts recalcitrant plant tissues into nutritious food, available to the ants through mycophagy. Fungus gardens also host a particular bacterial community, potentially involved in nutrient cycling. To what extent the microbiota aid in the lignocellulolytic capacity of the fungus garden, and possible biotechnological applications of this potential remain unclear. Here, we propose a multidisciplinary approach to evaluate the microbial drivers of plant biomass breakdown in fungus gardens of the leaf-cutting attine ant Atta sexdens. We aim to characterize the plant biomass degradation in these systems by determining its metabolic flexibility, lignocellulolytic efficiency ex situ, and the metabolic complementarity between the symbiotic fungus and the bacterial community to decompose lignocellulose. We also intend to address whether putative lignocellulolytic pathways could be applied to decompose even more recalcitrant substrates, as low density polyethylene (LDPE) and polyethylene terephthalate (PET). By coupling metagenomics, metatranscriptomics, nuclear magnetic resonance (NMR), confocal microscopy, and DNA-SIP tools, this proposal seeks to elucidate pathways for depolimerization of recalcitrant substrates in a multipartite symbiotic system. Besides shedding light on key processes of the attines nutritional ecology, the findings of this study could inspire alternatives to explore the biotechnological potential of a microbial consortium for degrading lignocellulosic and plastic residues.