Fungi in the Antarctic Cryosphere: Using DNA Metabarcoding to Reveal Fungal Diversity in Glacial Ice from the Antarctic Peninsula Region.

Graciéle Cunha Alves De Menezes,Micheline Carvalho-Silva,Paulo E A S Câmara,Peter Convey,Jefferson Cardia Simões,Otávio Henrique Bezerra Pinto,Luiz Henrique Rosa,Carlos Augusto Rosa

doi:10.1007/s00248-021-01792-x

Abstract

We assessed fungal diversity present in glacial from the Antarctic Peninsula using DNA metabarcoding through high-throughput sequencing (HTS). We detected a total of 353,879 fungal DNA reads, representing 94 genera and 184 taxa, in glacial ice fragments obtained from seven sites in the north-west Antarctic Peninsula and South Shetland Islands. The phylum Ascomycota dominated the sequence diversity, followed by Basidiomycota and Mortierellomycota. Penicillium sp., Cladosporium sp., Penicillium atrovenetum, Epicoccum nigrum, Pseudogymnoascus sp. 1, Pseudogymnoascus sp. 2, Phaeosphaeriaceae sp. and Xylaria grammica were the most dominant taxa, respectively. However, the majority of the fungal diversity comprised taxa of rare and intermediate relative abundance, predominately known mesophilic fungi. High indices of diversity and richness were calculated, along with moderate index of dominance, which varied among the different sampling sites. Only 26 (14%) of the total fungal taxa detected were present at all sampling sites. The identified diversity was dominated by saprophytic taxa, followed by known plant and animal pathogens and a low number of symbiotic fungi. Our data suggest that Antarctic glacial ice may represent a hotspot of previously unreported fungal diversity; however, further studies are required to integrate HTS and culture approaches to confirm viability of the taxa detected.

Highlights

Despite its generally extreme conditions, Antarctica hosts diverse environments
We detected a total of 353,879 fungal DNA reads, representing 94 genera and 184 distinct taxa in glacial ice obtained from the seven sampling locations in the South Shetland Islands and north-west Antarctic Peninsula
Our data suggest that Antarctic glacial ice may host a hotspot of as yet unreported fungal diversity

Summary

Introduction

Despite its generally extreme conditions, Antarctica hosts diverse environments. Microorganisms dominate many of the most extreme environments of the continent [1, 2, 3]. Fungi are amongst the microorganisms reported from the Antarctic cryosphere [6] Despite their recognised importance for ecosystem functioning in Antarctica and elsewhere, few studies have attempted to recover and identify fungal species from glacial ice and, until now, few species, mainly representing the phyla Ascomycota, Basidiomycota and Mortirellomycota, have been characterized from this environment [7, 8, 9, 10, 11, 12]. We assessed the fungal diversity, richness, abundance and distribution in glacial ice sampled in the different Antarctic sites using DNA metabarcoding high throughput sequencing (HTS)

Methods

Results

Discussion

Conclusion