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Title: Diversity and N2O Production Potential of Fungi in an Oceanic Oxygen Minimum Zone
Fungi in terrestrial environments are known to play a key role in carbon and nitrogen biogeochemistry and exhibit high diversity. In contrast, the diversity and function of fungi in the ocean has remained underexplored and largely neglected. In the eastern tropical North Pacific oxygen minimum zone, we examined the fungal diversity by sequencing the internal transcribed spacer region 2 (ITS2) and mining a metagenome dataset collected from the same region. Additionally, we coupled 15N-tracer experiments with a selective inhibition method to determine the potential contribution of marine fungi to nitrous oxide (N2O) production. Fungal communities evaluated by ITS2 sequencing were dominated by the phyla Basidiomycota and Ascomycota at most depths. However, the metagenome dataset showed that about one third of the fungal community belong to early-diverging phyla. Fungal N2O production rates peaked at the oxic–anoxic interface of the water column, and when integrated from the oxycline to the top of the anoxic depths, fungi accounted for 18–22% of total N2O production. Our findings highlight the limitation of ITS-based methods typically used to investigate terrestrial fungal diversity and indicate that fungi may play an active role in marine nitrogen cycling.  more » « less
Award ID(s):
1756947 1635562
NSF-PAR ID:
10217815
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Fungi
Volume:
7
Issue:
3
ISSN:
2309-608X
Page Range / eLocation ID:
218
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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