Antarctic fungi in a changing world: Metabolomic responses to abiotic stress associated with the effects of climate change

• Grant number: 24/00341-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2025
• End date: March 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Ian Castro-Gamboa
• Grantee: Gustavo Souza dos Santos
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 13/07600-3 - CIBFar - Center for Innovation in Biodiversity and Drug Discovery, AP.CEPID

Abstract

Antarctica represents one of the last frontiers on Earth. Its climate conditions include low temperatures, a high incidence of ultraviolet radiation during the summer, a lack of sunlight during the winter, and strong seasonal shifts in ice cover. Despite the extreme climate, Antarctica harbors a unique biodiversity dominated by endemic species adapted to the cold. To survive these conditions, microorganisms, such as fungi, have evolved distinct metabolic pathways, resulting in the biosynthesis of specialized metabolites used as an adaptation strategy. Despite its geographical isolation, Antarctica is particularly affected by the effects of climate change. In recent decades, the region has experienced significant warming, leading to glacier melting, rising air and ocean temperatures, and changes in biodiversity. Knowledge of the Antarctic microbiome is still limited. Moreover, the impact of abiotic stresses resulting from climate change, such as temperature elevation and changes in salinity, on the metabolome of Antarctic fungi has yet to be investigated. It is also unknown whether these effects may trigger the production of mycotoxins that pose risks to human, animal, and crops health. Therefore, the aim of this project is to explore the effects of temperature increases and salinity changes on the metabolome of Antarctic fungi isolated from permafrost, glacial ice, snow, and marine macroalgae. The fungi will be cultivated both axenically and in consortia, in various growth media, and subjected to temperature and salinity variations. Traditional approaches in chemical ecology, such as bioguided fractionation, do not allow the simultaneous investigation of numerous organisms and involve multiple steps. To overcome this challenge, we propose a workflow that combines ultra-high-resolution liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) with cutting-edge computational tools such as molecular networking (GNPS-MN), INVENTA, FERMO and MicrobeMASST to visualize the chemical diversity and metabolome shifts of the fungi in response to abiotic stress and cultivation conditions. 1H NMR combined with multivariate statistical analyses (PCA, PLS-DA, and OPLS-DA) will be used to support the HRMS data. Through the results that will be obtained in this project, we aim to provide new insights into the chemosystematics and chemo-dynamics of Antarctic fungi in the context of climate change, particularly for those endemic fungi that have not yet been chemically described. Our findings will enhance our understanding of chemical diversity in Antarctica. Furthermore, in light of the impending loss of biodiversity in Antarctica due to the effects of climate change, prospecting Antarctic fungi emerges as a tool for the conservation of these ecosystems.