MYCO-CARB sampled a range of marine ecosystems, including in the Atlantic Ocean and at the long term coastal marine observatories off Plymouth (UK). We also undertook a year-long seasonal transect from the coastal marine sites off Plymouth along an adjacent estuarine – freshwater gradient. Marine ecosystem sampling was supplemented with additional samples gifted from collaborators and other cruises including from polar regions and the Southern Ocean, and a unique preexisting eDNA time-series. DNA and RNA based assessment of marine fungal diversity was successful, including development and optimization of metabarcoding approaches for marine fungi.
We developed an innovative approach to study active saprotrophic fungi associated with marine particles. Individual organic particles were isolated from seawater, assessed via microscopy and subsequently used for single particle RNA extraction. From the single particle RNA, we were able to determine the activity of attached saprotrophic fungi. We also undertook alternative strategies to explore the potential for active fungal saprotrophy in the open ocean using high volume bulk in situ filtration and subsequent RNA-based assessment of fungal activity.
Over 500 strains have been successfully isolated from seawater, sediments and seaweeds, including from the open Atlantic Ocean, Antarctic and Arctic. All strains have been identified and are maintained cryopreserved at the Marine Biological Association. Strains from the collection have been used to explore the biology of marine fungi (summarised below) and are a resource for future research.
We explored the fundamental biology of saprotrophic marine fungi, including determining substrate ranges and responses to experimental variables across a range of marine fungal isolates. On selected models, we have shown how marine fungi are adapted. Selected models from the culture collection have undergone genome sequencing. We also worked on saprotrophic chytrid fungi, including determining interaction with particulate organic matter, aspects of the chytrid cell cycle and role of chytrids in particle microbiome interaction.