Insights into fungal diversity of a shallow-water hydrothermal vent field at Kueishan Island, Taiwan by culture-based and metabarcoding analyses

Abstract

This paper reports the diversity of fungi associated with substrates collected at a shallow hydrothermal vent field at Kueishan Island, Taiwan, using both culture-based and metabarcoding methods. Culture of fungi from yellow sediment (with visible sulfur granules), black sediment (no visible sulfur granules), the vent crab Xenograpsus testudinatus, seawater and, animal egg samples resulted in a total of 94 isolates. Species identification based on the internal transcribed spacer regions of the rDNA revealed that the yellow sediment samples had the highest species richness with 25 species, followed by the black sediment (23) and the crab (13). The Ascomycota was dominant over the Basidiomycota; the dominant orders were Agaricales, Capnodiales, Eurotiales, Hypocreales, Pleosporales, Polyporales and Xylariales. Hortaea werneckii was the only common fungus isolated from the crab, seawater, yellow and black sediment samples. The metabarcoding analysis amplifying a small fragment of the rDNA (from 18S to 5.8S) recovered 7–27 species from the black sediment and 12–27 species from the yellow sediment samples and all species belonged to the Ascomycota and the Basidiomycota. In the yellow sediments, the dominant order was Pleosporales and this order was also dominant in the black sediment together with Sporidiobolales. Based on the results from both methods, 54 and 49 species were found in the black and yellow sediments, respectively. Overall, a higher proportion of Ascomycota (~70%) over Basidiomycota was recovered in the yellow sediment and the two phyla were equally abundant in the black sediment. The top five dominant fungal orders in descending order based on species richness were Pleosporales>Eurotiales>Polyporales>Hypocreales>Capnodiales in the black sediment samples, and Polyporales>Pleosporales>Eurotiales>Capnodiales>Hypocreales in the yellow sediment samples. This study is the first to observe a high diversity of fungi associated with various substrates at a marine shallow water hydrothermal vent ecosystem. While some fungi found in this study were terrestrial species and their airborne spores might have been deposited into the marine sediment, several pathogenic fungi of animals, including Acremonium spp., Aspergillus spp., Fusarium spp., Malassezia spp., Hortaea werneckii, Parengyodontium album, and Westerdykella dispersa, were recovered suggesting that these fungi may be able to cause diseases of marine animals.

Meta‐omics highlights the diversity, activity and adaptations of fungi in deep oceanic crust

“…Here we report a total of 59 fungal genera detected using a combination of culture‐dependent and ‐independent methods. Most of them are identified as Penicillium , Aspergillus , Cladosporium and Debaryomyces , all ubiquitous taxa commonly detected in deep‐sea and deep‐subsurface habitats using marker gene (Tedersoo et al ., 2015; Li et al ., 2016, 2019; Pang et al ., 2019; Polinski et al ., 2019) and culture‐based approaches (Nagano et al ., 2010, 2017; Manohar et al ., 2014; Hirayama et al ., 2015; Zhang et al ., 2016). While it is possible that some fraction of this diversity may exist as spores and therefore may not be metabolically active, their consistent detection in these habitats strongly suggests the environmental relevance of at least some fraction of this community to the deep biosphere.…”

Whole Genome Sequencing and Comparative Genome Analysis of the Halotolerant Deep Sea Black Yeast Hortaea werneckii

“…The presence of the fungus was demonstrated also in other deep-sea environments, such as deep-sea hydrothermal ecosystems in the Pacific Ocean [ 22 , 24 ] and sediments at 5000 m depths in the Central Indian Basin [ 23 ]. However, the species is not currently considered a marine fungus [ 21 ].…”

“…Although H. werneckii is not listed as a marine species [ 21 ], it is stated that it also occurs in marine habitats, and also in the depths of the oceans [ 22 , 23 , 24 ].…”

Fungal symbionts of Arctic zooplankton induce mortality and reduce swimming activity

“…Marine fungi are globally distributed (Tisthammer et al 2016; Hassett et al 2019b; Morales et al 2019) and comprise comparable quantities of biomass (~1 mg Cm -3 ) as other abundant marine taxa (Damare and Raghukumar 2008; Gutiérrez et al 2011; Bochdansky et al 2017; Hassett et al 2019a). Increasing quantities of diverse lines of evidence underscore that fungi are nearly ubiquitous in the marine realm (Burgaud et al 2009; Edgcomb et al 2011; Orsi et al 2013; Taylor and Cunliffe 2016; Li et al 2018; Garvetto et al 2019; Pang et al 2019), including throughout the Arctic (Sparrow 1973; Pang et al 2008; Terrado et al 2011; Zhang et al 2015; Hassett and Gradinger 2016; Hassett et al 2019a). Fungi are diverse (Kagami et al 2014) and many marine taxa represent novel, ecologically uncharacterized lineages(Richards et al 2012; Ettinger and Eisen 2019), including in the Arctic Ocean (Comeau et al 2016; Hassett et al 2017).…”