Heads in the clouds: marine viruses disperse bidirectionally along the natural water cycle

Rahlff, J.; Esser, S. P.; Plewka, J.; Heinrichs, M. E.; Soares, A.; Scarchilli, C.; Grigioni, P.; Wex, H.; Giebel, H.-A.; Probst, A. J.

doi:10.1101/2022.06.21.497027

bioRxiv · 10.1101/2022.06.21.497027

Heads in the clouds: marine viruses disperse bidirectionally along the natural water cycle

Rahlff, J.·Esser, S. P.·Plewka, J.·Heinrichs, M. E.·Soares, A.·Scarchilli, C.·Grigioni, P.·Wex, H.·Giebel, H.-A.·Probst, A. J.

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Abstract

Marine viruses have thoroughly been studied in seawater, yet their dispersal from neuston ecosystems at the air-sea interface towards the atmosphere remains a knowledge gap. Here, we show that 6.2 % of the studied virus population were shared between air-sea interface ecosystems and rainwater. Virus enrichment in the 1-mm thin surface microlayer and sea foams happened selectively, and variant analysis proved virus transfer to aerosols and rain. Viruses detected in rain and aerosols showed a significantly higher percent G/C base content compared to marine viruses, and a genetically distinct rain virome supports that those viruses could inhabit higher air masses. CRISPR spacer matches of marine prokaryotes to "foreign" viruses from rainwater prove regular virus-host encounters at the air-sea interface. Our findings on aerosolization and long-range atmospheric dispersal implicate virus-mediated carbon turnover in remote areas, viral dispersal mechanisms relevant to human health, and involvement of viruses in atmospheric processes like ice-nucleation.

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Rahlff, J., Esser, S. P., Plewka, J., Heinrichs, M. E., Soares, A., Scarchilli, C., Grigioni, P., Wex, H., Giebel, H.-A., Probst, A. J.. 2022-06-22. Heads in the clouds: marine viruses disperse bidirectionally along the natural water cycle. https://doi.org/10.1101/2022.06.21.497027

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