Photosynthetic cryptophytes are ubiquitous protists that are major participants in the freshwater phytoplankton bloom at the onset of spring. Mortality due to change in environmental conditions and grazing have been recognized as key factors contributing to bloom collapse. In contrast, the role of viral outbreaks as factors terminating phytoplankton blooms remains unknown from freshwaters. Here, we isolated and characterized a cryptophyte virus contributing to the annual collapse of a natural cryptophyte spring bloom population. This viral isolate is also representative for a clade of abundant giant viruses (phylum Nucleocytoviricota) found in freshwaters all over the world.

Department of Aquatic Microbial Ecology Institute of Hydrobiology Biology Centre of the Czech Academy of Sciences 37005 České Budějovice Czech Republic

Department of Fisheries Oceanography and Marine Ecology National Marine Fisheries Research Institute 81 332 Gdynia Poland

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Sommer U, Adrian R, De Senerpont DLet al. . Beyond the plankton ecology group (PEG) model: mechanisms driving plankton succession. Annu Rev Ecol Evol Syst 2012;43:429–48. 10.1146/annurev-ecolsys-110411-160251 DOI

Kavagutti VS, Bulzu P-A, Chiriac CMet al. . High-resolution metagenomic reconstruction of the freshwater spring bloom. Microbiome 2023;11:15. 10.1186/s40168-022-01451-4 PubMed DOI PMC

La Scola B, Audic S, Robert Cet al. . A giant virus in amoebae. Science 2003;299:2033. 10.1126/science.1081867 PubMed DOI

Gallot-Lavallée L, Blanc G, Claverie J-M. Comparative genomics of Chrysochromulina ericina virus and other microalga-infecting large DNA viruses highlights their intricate evolutionary relationship with the established Mimiviridae family. J Virol 2017;91. 10.1128/JVI.00230-17 PubMed DOI PMC

Garza DR, Suttle CA. Large double-stranded DNA viruses which cause the lysis of a marine heterotrophic nanoflagellate (Bodo sp.) occur in natural marine viral communities. Aquat Microb Ecol 1995;9:203–10. 10.3354/ame009203 DOI

Sun T-W, Yang C-L, Kao T-Tet al. . Host range and coding potential of eukaryotic giant viruses. Viruses 2020;12:1337. 10.3390/v12111337 PubMed DOI PMC

Šimek K, Mukherjee I, Szöke-Nagy Tet al. . Cryptic and ubiquitous aplastidic cryptophytes are key freshwater flagellated bacterivores. ISME J 2023;17:84–94. 10.1038/s41396-022-01326-4 PubMed DOI PMC

Pienaar RN. Virus-like particles in three species of phytoplankton from San Juan Island. Washington Phycologia 1976;15:185–90. 10.2216/i0031-8884-15-2-185.1 DOI

Suttle CA, Chan AM, Cottrell MT. Use of ultrafiltration to isolate viruses from seawater which are pathogens of marine phytoplankton. Appl Environ Microbiol 1991;57:721–6. 10.1128/aem.57.3.721-726.1991 PubMed DOI PMC

Nagasaki K, Kim J-J, Tomaru Yet al. . Isolation and characterization of a novel virus infecting Teleaulax amphioxeia (Cryptophyceae). Plankton Benthos Res 2009;4:122–4. 10.3800/pbr.4.122 DOI

Xia Y, Cheng H, Zhong J. Hybrid sequencing resolved inverted terminal repeats in the genome of Megavirus Baoshan. Front Microbiol 2022;13:831659. 10.3389/fmicb.2022.831659 PubMed DOI PMC

Schwarzer D, Stummeyer K, Gerardy-Schahn Ret al. . Characterization of a novel intramolecular chaperone domain conserved in endosialidases and other bacteriophage tail spike and fiber proteins. J Biol Chem 2007;282:2821–31. 10.1074/jbc.M609543200 PubMed DOI

Aylward FO, Moniruzzaman M, Ha ADet al. . A phylogenomic framework for charting the diversity and evolution of giant viruses. PLoS Biol 2021;19:e3001430. 10.1371/journal.pbio.3001430 PubMed DOI PMC

Schvarcz CR, Steward GF. A giant virus infecting green algae encodes key fermentation genes. Virology 2018;518:423–33. 10.1016/j.virol.2018.03.010 PubMed DOI

Rozenberg A, Oppermann J, Wietek Jet al. . Lateral gene transfer of anion-conducting Channelrhodopsins between green algae and giant viruses. Curr Biol 2020;30:4910–4920.e5. 10.1016/j.cub.2020.09.056 PubMed DOI

Blow MJ, Clark TA, Daum CGet al. . The Epigenomic landscape of prokaryotes. PLoS Genet 2016;12:e1005854. 10.1371/journal.pgen.1005854 PubMed DOI PMC

Jeudy S, Rigou S, Alempic J-Met al. . The DNA methylation landscape of giant viruses. Nat Commun 2020;11:2657. 10.1038/s41467-020-16414-2 PubMed DOI PMC