Viruses under the Antarctic Ice Shelf are active and potentially involved in global nutrient cycles

• Published in: Nature Communications
• Main Authors: Lopez-Simon, Javier, Vila-Nistal, Marina, Rosenova, Aleksandra, De Corte, Daniele, Baltar, Federico, Martinez-Garcia, Manuel
• Other Authors: Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio "Ramón Margalef", Ecología Microbiana Molecular
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2023
• Subjects: Viruses; Antarctic Ice Shelf; Global nutrient cycles; Antarctic; New Zealand; Ross Ice Shelf; The Antarctic; Antarc*; Ice Shelf; Ice Shelves
• Online Access: http://hdl.handle.net/10045/139186; https://doi.org/10.1038/s41467-023-44028-x

Viruses play an important role in the marine ecosystem. However, our comprehension of viruses inhabiting the dark ocean, and in particular, under the Antarctic Ice Shelves, remains limited. Here, we mine single-cell genomic, transcriptomic, and metagenomic data to uncover the viral diversity, biogeography, activity, and their role as metabolic facilitators of microbes beneath the Ross Ice Shelf. This is the largest Antarctic ice shelf with a major impact on global carbon cycle. The viral community found in the cavity under the ice shelf mainly comprises endemic viruses adapted to polar and mesopelagic environments. The low abundance of genes related to lysogenic lifestyle (<3%) does not support a predominance of the Piggyback-the-Winner hypothesis, consistent with a low-productivity habitat. Our results indicate a viral community actively infecting key ammonium and sulfur-oxidizing chemolithoautotrophs (e.g. Nitrosopumilus spp, Thioglobus spp.), supporting a “kill-the-winner” dynamic. Based on genome analysis, these viruses carry specific auxiliary metabolic genes potentially involved in nitrogen, sulfur, and phosphorus acquisition. Altogether, the viruses under Antarctic ice shelves are putatively involved in programming the metabolism of ecologically relevant microbes that maintain primary production in these chemosynthetically-driven ecosystems, which have a major role in global nutrient cycles. We thank the research grant to MMG funded by the Spanish Ministry of Science and Innovation and Agencia Estatal de Investigación (PID2021-125175OB-I00). We also thank the Victoria University of Wellington Hot Water Drilling Team led by A. Pyne and D. Mendeno. This research was facilitated by the New Zealand Antarctic Research Institute (NZARI) funded Aotearoa New Zealand Ross Ice Shelf Programme, the New Zealand Antarctic Science Platform ANTA1801, the Austrian science fond (FWF) projects OCEANIDES (P34304-B), ENIGMA (TAI534), EXEBIO (P35248), and OCEANBIOPLAST (P35619-B) and a Rutherford Discovery Fellowship ...