Fungal Diversity Associated with an Active Deep Sea Volcano: Vailulu'u Seamount, Samoa

Active undersea volcanoes generate complex hydrothermal environments that provide microbial habitats rich in reduced metals. These habitats harbor a substantial microbial communities functionally capable of Fe(II) and Mn(II) oxidation. The role of eukaryotes in these settings remains largely unknown. We explored the presence of fungi in actively growing Fe-oxide mats and basalt rock surfaces from the active volcano, Vailulu'u seamount (Samoan chain). Here we document the presence of a diverse fungal community including eight yeasts and yeast-like fungal species isolated from cold hydrothermal environments and basalt rock surfaces. Many of the isolates produce siderophores, a class of molecules used to acquire and utilize Fe (III), and one isolate, Rhodotorula graminis oxidizes Mn(II). These results suggest that fungi may also play a functional role in seafloor alteration and biomineralization processes.