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bioRxiv · 10.1101/623272

Highly diverse fungal communities in carbon-rich aquifers of two contrasting lakes in Northeast Germany

Perkins, A.·Ganzert, L.·Rojas-Jimenez, K.·Fonvielle, J.·Hose, G.·Grossart, H.-P.
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Abstract

Fungi are an important component of microbial communities and are well known for their ability to degrade refractory, highly polymeric organic matter. In soils and aquatic systems, fungi play an important role in carbon processing, however, their diversity, community structure and function as well as ecological role, particularly in groundwater, are poorly studied. The aim of this study was to examine the fungal community composition, diversity and function of 16 groundwater boreholes located in the vicinity of two lakes in NE Germany that are characterized by contrasting trophic status. The analysis of 28S rRNA gene sequences amplified from the groundwater revealed high fungal diversity and clear differences in community structure between both aquifers. Most sequences were assigned to Ascomycota and Basidiomycota, but members of Chytridiomycota, Cryptomycota, Zygomycota, Blastocladiomycota, Glomeromycota and Neocallmastigomycota were also detected. In addition, 27 species of fungi were successfully isolated from the groundwater wells and tested for their ability to degrade complex organic polymers - the predominant carbon source in the wells. Most isolates showed positive activities for at least one of the tested polymer types, with three strains, belonging to the genera Gibberella, Isaria and Cadophora, being able to degrade all tested substrates. Our results highlight the high diversity of fungi in groundwater, and point to their important ecological role in breaking down highly polymeric organic matter in these isolated microbial habitats.

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Perkins, A., Ganzert, L., Rojas-Jimenez, K., Fonvielle, J., Hose, G., Grossart, H.-P.. 2019-04-30. Highly diverse fungal communities in carbon-rich aquifers of two contrasting lakes in Northeast Germany. https://doi.org/10.1101/623272

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